Apparently he wanted to make sure that he would kill, and thereby increase his chances to gaining the place in Paradise that Allah guarantees to those who “kill and are killed” (Qur’an 9:111).
From AFP :
PESHAWAR – The suicide bomber who killed 54 people in a Pakistan mosque had packed his explosives vest with ball bearings to inflict maximum casualties, a hospital official said on Saturday.
With security agencies hunting for clues to Friday”s attack, which targeted but missed a close ally of President Pervez Musharraf, a doctor said many of the victims suffered severe shrapnel wounds.
“Many were hit by ball bearings packed into the bomber’s suicide jacket,” said Manzoor Khan of the main state-run hospital in the northwest town of Charshadda, where the attack occurred.
“It seems most of the victims died from excessive bleeding,” he told AFP.