Doug Mills, a veteran photographer for The New York Times who has been taking photographs of presidents since 1983, was only feet away from former President Donald J. Trump at the rally in Butler, Pa., when shooting started.

He spoke with Victor Mather about the experience.

What did you see and hear today?

It was a very standard, typical rally. The former president was maybe an hour late. The crowd had been hot all day. Donald J. Trump arrived, waving to the crowd, just like any other rally he does.

There’s a pool of photographers, maybe four of us, who were in what is called the buffer area just a couple feet from the former president. We were all jostling around in there trying to get our normal pictures.

All of a sudden, there was what I thought were three or four loud pops. At first I thought it was a car. The last thing I thought was it was a gun.

I kept taking pictures. He went down behind the lectern, and I thought, “Oh my God, something’s happened.”