Kandahar, Afghanistan ? A bomb strapped to a bicycle killed 13 people Tuesday in this southern Afghan city, most of them children who halted a soccer game and rushed to the site after an initial explosion.

The treacherous double blast, blamed on Taliban militants, may have been intended to lure U.S. troops or hit the provincial governor. But it was innocents who died — another bloody reminder of the violence sweeping Afghanistan two years after the Taliban’s fall.

The death toll put a brutal end to celebrations of a new constitution feted as a bulwark against terrorism, and highlighted the task facing American forces gearing up for a new offensive in time for summer elections.

Curiosity got the better of the children after the first blast tossed bicycles parked on the roadside. The second bomb, a few minutes later at the same spot, was devastating.

The city’s deputy police chief, Salim Khan, said the truck driver and a male passer-by were also killed by the second bomb, which he said was attached to one of the bicycles.

Police said eight children, ages 7 to 15, died at the scene, and three more died later of their wounds. Critical cases were rushed to a U.S. military base at Kandahar Air Field for treatment.

Officials said two men were arrested, one of them caught running from the scene.

Khan, whose men were interrogating at least one of the suspects, made clear he suspected Taliban or al-Qaida in the attack.

“The investigation is only just beginning,” he said. “But we all know the enemies of Afghanistan.”

Afghani Saami Khan recuperates in a hospital after he was injured by a bomb while playing in the streets in Kandahar, Afghanistan. A bomb attached to a bicycle killed 13 people, most of them children, Tuesday, underlining the violence still plaguing Afghanistan two years after the fall of the Taliban.