London's Olympic Stadium witnessed its first world record on Tuesday when British wheelchair racer Hannah Cockroft set a new mark in the T34 category for 100m.

Competing at a Paralympic test event just days after the official opening of the 80,000-seat venue, the 19-year-old world champion stopped the clock at 18.56 sec.

Ireland's Michael McKillop then became the first male to set a world record on the track when he slashed 15 sec off his own record in the T37 category 1,500.

"Incredible is the word," Cockroft said.

"I didn't come here expecting anything amazing at all. I had no idea I was near world-record pace."

Her day did not go entirely to plan, however, as she suffered some transport problems arriving at the east London Olympic Park and had to jump in a taxi.

"The morning was really stressful, the bus broke down and then they wouldn't let the taxis in," she said.

"I missed the warmup and had to just get my numbers on and go straight onto the track. It was the worst preparation I'd ever had before a race."

Ireland's McKillop, a gold medalist in Beijing, played down his achievement.

"It's nice to be here and breaking a world record. Being the first male to do it in this stadium is quite a nice thought," he said after finishing in 3:59.54.

"It's only a 400 track with lots of seats around it basically, so it's similar to where I train which is also a 400m track. I've just got to get used to it."

The stadium, the heart of the London Olympics, has been hosting test events since last Friday when the British Universities and Colleges outdoor championships took place.

Reuters