A man suspected of shouting abuse and hurling a bottle onto the track at the start of the men's 100m final at the Olympic Stadium has been arrested.
Speaking after the race - which was won by Jamaica's Usain Bolt - US sprinter Justin Gatlin, who won bronze, said: "It was a little distraction and I didn't know what it was.
"But when you're in those blocks and the whole stadium's quiet you can hear a pin drop."
Bolt told reporters he had been unaware of the incident.
He added: "No, I keep hearing that. I don't know who would have done that."
Fellow Jamaican Yohan Blake said: "I was so focused I didn't see anything. I was so focused on just running to the line."
Edith Bosch, the Netherlands' world judo champion, said on Twitter that she had "beaten" the person who had thrown the bottle.
She tweeted: "A drunken spectator threw a bottle onto the track! I HAVE BEATEN HIM .... unbelievable."
Nobody was injured during the incident and the event was not disrupted, police said.
The suspect is being held in police custody at an east London police station on suspicion of causing a public nuisance.
Gatlin said the incident had not affected the race, explaining: "You just have to block it out and go out there and do what you got to do.
"You can't complain about that, the race went on and it was a great race."