I went to the road just outside Ramallah, as on previous days, because that is one of the places in the West Bank where Palestinians have been protesting against U.S. President Donald Trump's recognition of Jerusalem as Israel's capital.
The 100-metre stretch leads from the city limits of Ramallah to the Jewish settlement of Beit El, and has a filling station and a traffic circle.
Earlier on Friday, which Palestinians were calling a "Day of Rage", I had tried working at the Kalandia crossing point into the West Bank, but the Israelis had thrown tear gas and I knew this would make taking good photographs difficult.
Outside Beit El, a group of paramilitary Israeli police had driven back hundreds of Palestinians who were throwing rocks and burning tyres. I was photographing the protesters, and did not see another Palestinian who apparently emerged close to the Israeli squad from a hiding place near the traffic circle.
I heard the Israeli police shooting, and turned around. On instinct, I started taking pictures, all the time trying to keep well out of the line of fire.
When the Palestinian fell, I could see that he was holding a knife, and wearing what looked like a suicide bomb vest.
Israeli police said he had managed to stab and wound one of their number before being shot. Palestinian medics later said the attacker was dead, and that his bomb belt had been fake.