I don’t think the guy did it...
.... he wouldn’t wait around a ‘ticking’ bomb...especially not close enough to be as injured with the burns they’ve reported he had....and not so foolish as to go to a hospital for assistance.
However the authorities have said “no stone unturned” which would include him and others as well.
My guess the attackers were probing the crowd looking for the most effective placement. The is a BOLO report looking for a person of interest that tried to access the bleacher area and was turned away.
Perhaps the detained Saudi lost track of time and the blast occurred while he was nearby guarding the bomb drop.
Almost certainly the bombs were on a timer. The detainee suffered a minor leg wound from shrapnel so he was nearly at a safe distance, took off running and was tackled by a citizen and held.
Will the FBI also interview the other 80,000 Saudi students?
Since he was caught at the scene and taken to the hospital under police guard, he didn't have much choice in the matter.
“I don’t think the guy did it...
.... he wouldn’t wait around a ‘ticking’ bomb...especially not close enough to be as injured with the burns they’ve reported he had....”
That is right. No one who has ever built a bomb has ever been hurt by it. Just like no one has ever been burned by a fire they have started or been shot by their own weapon...
You’ve heard of suicide bummers? And you’ve heard that not all are much for competent? Thinking underwear and tennis shoes so far.