The only videotape known to have captured both planes slamming into the World Trade Center, and only the second image of the first strike, has surfaced days before the second anniversary of the Sept. 11, 2001, attacks.

The footage, obtained by The New York Times, was taken by a Czech immigrant construction worker whose son at one point came close to accidentally erasing the rare, chilling footage, the newspaper reported on its Web site Saturday.

Federal officials investigating the trade center collapse are trying to obtain a copy of the hour-long tape, which could cast light on the cause of the north tower’s collapse by helping to determine factors including the exact speed at which the first plane traveled, The Times said.

The only other known footage of the first plane’s impact came from a French film crew making a documentary about a probationary firefighter.