Bangladesh ? A suicide bomber on a bicycle rode into a crowd and detonated his explosives Thursday, killing six people and wounding dozens, police and witnesses said.

Police said a second bomber who failed to detonate his explosives was among the wounded.

A crowd of about 400 people had gathered to watch police defuse a bomb found earlier when the suicide attacker struck, spraying onlookers with shrapnel, witnesses said.

Police officials blamed the attack on Jumatul Mujahideen Bangladesh, a banned Islamic militant group implicated in a string of recent blasts. The explosion brought the death toll from the bombings in the last two weeks to 21.

At least 45 people, including nine police officers and the second suspected bomber, were injured.