Mexico’s government says it will send 6,000 troops to its southern border with Guatemala in a crackdown on Central American migrants hoping to seek asylum in the U.S. Thursday’s announcement came as heavily armed Mexican soldiers and police blocked a caravan of about a thousand migrants as they walked a highway in the southern state of Chiapas. The crackdown came ahead of a threat by President Trump to impose 5% tariffs on all Mexican imports next Monday unless Mexico further tightens controls on immigration. Mexican officials are reportedly nearing a deal with the White House that would require asylum seekers to seek refuge in the countries they first cross into. Under the plan, Guatemalan migrants could only apply for asylum in Mexico; Hondurans and Salvadorans would be forced to apply as refugees in Guatemala. The emerging plan drew fire from civil liberties groups including the ACLU, which said such a change to the asylum system violates both U.S. and international laws and is unlikely to survive a legal challenge.

Democratic House Judiciary Chair Jerrold Nadler is preparing to subpoena special counsel Robert Mueller within the next two weeks. That’s according to Politico, which also reports Nadler is privately pushing Democratic leaders to open a formal impeachment inquiry against the president. During a closed-door meeting on Tuesday, House Speaker Nancy Pelosi reportedly pushed back, saying Trump should be “in prison”—but not impeached.

Meanwhile, the Democratic chair of the House Ways and Means Committee is coming under fire from his own party after he told Bloomberg News he has no plans to use a recently passed New York state law to acquire President Trump’s tax records. Congressmember Richard Neal says he’s worried the request would “bolster Trump administration arguments that Congress is on a political fishing expedition.” Treasury Secretary Steven Mnuchin has defied congressional requests to turn over Trump’s tax records, and Trump remains the only president or major presidential candidate in modern U.S. history to refuse to make tax returns public.

Russian President Vladimir Putin warned Thursday of a “global catastrophe” if the Trump administration abandons talks on extending the New START nuclear arms treaty. The agreement—negotiated by the Obama administration in 2010 and ratified by the Senate later that year—limits the total number of deployed nuclear warheads, missiles and bombers. It’s set to expire in 2021, and so far Putin says the U.S. has ignored his efforts to negotiate an extension.

President Vladimir Putin: “No one has spoken with us. No formal process of talks is taking place. And it will all end in 2022.”

In February, the Trump administration withdrew the U.S. from another landmark nuclear deal: the 1987 Intermediate-Range Nuclear Forces Treaty, or INF. The move prompted Russia to withdraw, as well, warning it was preparing a new generation of nuclear-capable missiles.

The African Union has suspended Sudan’s membership, after soldiers with the ruling Transitional Military Council opened fire on sit-in protesters on Monday, killing at least 108 people and wounding more than 500 others. In a statement, the AU said Sudan would remain suspended until a civilian-led transitional authority is established. Sudan’s military took power in April after a month-long popular uprising led to the overthrow of longtime authoritarian President Omar al-Bashir.

A new study finds climate change could cause thousands of heat-related deaths across the United States each year if global greenhouse gas emissions aren’t rapidly curbed. The study in the journal Science Advances looked at deaths from recent heat waves in 15 major U.S. cities, extrapolating mortality rates from future temperature rise. In New York City alone, a global temperature rise of 3 degrees Celsius—or 5.4 degrees Fahrenheit—could mean another 5,800 deaths each year; with another 2,500 extra annual deaths in Los Angeles.

Washington governor and 2020 presidential hopeful Jay Inslee says the Democratic National Committee is refusing to schedule a candidate debate on the climate crisis. Inslee said Thursday he was told by the DNC that if he participates in any non-DNC-affiliated debate on the climate, he would be disinvited to future debates held by the committee. Inslee called the move a “deeply disappointing” attempt to blacklist candidates. He said in a statement, “The DNC is silencing the voices of Democratic activists, many of our progressive partner organizations, and nearly half of the Democratic presidential field, who want to debate the existential crisis of our time.”

The Service Employees International Union has become the first U.S. labor union to support the Green New Deal. On Thursday, SEIU’s executive board voted to endorse the plan to radically shift the U.S. economy to renewable energy, ending U.S. carbon dioxide emissions by 2030. In a tweet, SEIU said, “This groundbreaking measure aims to address climate change while creating high-quality union jobs. We need to combat climate change while raising standards for all working people.”

A new scientific paper warns the Earth’s oceans are even more contaminated with microplastic pollution than previously known. The study, whose findings appear in Thursday’s edition of Nature Scientific Reports, sampled vertical columns of water off California extending to the deep ocean floor. The findings revealed tiny pieces of plastic waste at every depth—with higher concentrations far below the surface. The study also found high levels of microplastic pollution in the bodies of crabs, fish and microscopic ocean animals. The findings counter the widespread belief that most plastic waste is found floating at the surface and near coastlines.

The Trump administration is planning to reclassify high-level radioactive waste as low-risk, in a bid to cut as much as $40 billion from cleanup costs at nuclear weapons production sites around the U.S. A top Energy Department official called the proposal a “responsible, results-driven solution” to the problem of nuclear waste disposal. The move was condemned by environmentalists and scientists who say the waste needs to be contained in facilities deep underground. In a statement, the Natural Resources Defense Council said, “The Trump administration is moving to fundamentally alter more than 50 years of national consensus on how the most toxic and radioactive waste in the world is managed and ultimately disposed of.”

Former Vice President Joe Biden on Thursday reversed his long-standing support for the Hyde Amendment, a decades-old ban on federal funding for abortions. Biden announced his policy shift at a fundraiser in Atlanta.

Joe Biden: “For many years as U.S. senator, I have supported the Hyde Amendment, like many, many others have, because there was sufficient moneys and circumstances where women were able to exercise that right—women of color, poor women, women who were not able to have access. And it was—it was not under attack as it was then—as it is now. But circumstances have changed.”

Biden’s reversal came during the same week that his campaign affirmed his support for the Hyde Amendment’s ban on federal funding for abortions. That set off a wave of criticism from grassroots Democrats, women’s rights groups and most of Biden’s rivals for the 2020 nomination.

Former New York City prosecutor Linda Fairstein has stepped down from Vassar College’s board of trustees and from the boards of a pair of nonprofits, amid growing outrage over her role in the case of the Central Park Five. In 1989, five teenagers of color from Harlem were wrongfully accused and convicted on charges of gang rape, based largely on Fairstein’s work as head of the Sex Crimes Unit for the Manhattan District Attorney’s Office. The five spent years in prison before the real perpetrator confessed in 2002. The case drew renewed attention after the recent premiere of the Netflix miniseries about the Central Park Five. After headlines, we’ll spend the rest of the hour with Ava Duvernay, director of “When They See Us.”

A New York Police Department disciplinary hearing wrapped up Thursday for Daniel Pantaleo, a white police officer who killed unarmed African American Eric Garner in 2014 by putting him in a chokehold and refusing to let go even as Garner repeatedly gasped “I can’t breathe.” Pantaleo never faced criminal prosecution, after a grand jury decided not to indict him. He has remained on the police force but could lose his job and pension if found guilty of violating NYPD procedures. A presiding judge will send a recommendation about Pantaleo’s fate to Police Commissioner James O’Neill in the coming weeks. Eric Garner’s mother, Gwen Carr, called Thursday for all the officers present at her son’s killing to be fired.

Meanwhile, the NYPD has apologized for the first time for its raid a half-century ago on the Stonewall Inn, a gay- and trans-friendly bar in Manhattan’s Greenwich Village. In June of 1969, the inn was the site of a violent police raid that triggered an uprising and helped launch the modern-day LGBTQ rights movement. On Thursday, NYPD Commissioner James O’Neill made the apology during a press briefing on public safety for Pride Month events.

Commissioner James O’Neill: “The actions taken by the NYPD were wrong—plain and simple. The actions and the laws were discriminatory and oppressive. And for that, I apologize.”

Washington state’s Supreme Court ruled Thursday against a florist who refused to provide floral arrangements for the wedding of a same-sex couple, ruling the business owner broke the state’s consumer protection and anti-discrimination laws. The ruling came almost exactly one year after the U.S. Supreme Court ruled in favor of Colorado baker Jack Phillips, who refused to make a wedding cake for a gay couple, citing his religious opposition.

In Las Vegas, an animal rights activist rushed the stage at a space technology conference Thursday to confront Amazon CEO Jeff Bezos over conditions at chicken farms that supply meat to Whole Foods and other Amazon grocery brands. The activist, Priya Sawhney, was quickly forced off the stage as she told the world’s richest man to stand up for the rights of animals. Sawhney is co-founder of the group Direct Action Everywhere, whose members work to directly rescue animals from factory farms and slaughterhouses. She was arrested in September at a protest against animal cruelty at the largest organic poultry producer in the U.S. and faces up to a decade in prison. Click here to see our interview with Priya Sawhney.

And legendary New Orleans musician Dr. John died Thursday of a heart attack. He was 77 years old. Dr. John won six Grammy Awards in a decades-long career that saw him produce at least three dozen albums fusing blues, boogie, funk and jazz—a flamboyant sound that embodied New Orleans’s diverse music scene. After Hurricane Katrina devastated New Orleans in 2005, Dr. John headlined a series of benefit concerts. In 2010, he was active in the campaign to hold BP accountable for the Deepwater Horizon oil disaster off the Louisiana coast.