The explosion at an ammunition depot west of Tehran occurred just days days after the U.N. International Atomic Energy Agency released a report raising new concerns over what it calls “possible military dimensions” to Iran’s nuclear activities. On Sunday, President Obama warned that no options are being taken off the table concerning Iran.

President Barack Obama: “The sanctions have enormous bite and enormous scope. And we’re building off the platform that has already been established. The question is, are there additional measures that we can take? And we’re going to explore every avenue to see if we can solve this issue diplomatically. I have said repeatedly, and I will say it today: We are not taking any options off the table.”