Police have arrested 13 people allegedly linked to a man who blew himself up in a Casablanca Internet cafe and found bomb-making equipment on Wednesday, an Interior Ministry spokesman said.

Like the bomber, at least one of those arrested had been in prison on terrorism charges before being pardoned, ministry spokesman Abderrahman Achour told The Associated Press.

Abdelfettah Raydi died when explosives hidden on his body went off in an internet cafe in the Casablanca slum of Sidi Moumen, injuring Raydi's accomplice, Youssef Khouidri, and three bystanders.

Khouidri fled, dropping a belt of explosives, but was arrested an hour later. Police have so far not been able to fully question Khouidri because of injuries to his throat, Achour said in a telephone interview.

Police in Casablanca discovered bomb-making material in a room where Raydi and Khouidri had lived for several weeks leading up to Sunday's blast, Achour said.

Further information on the find or the arrests was not immediately available.

The ministry spokesman said the pair had probably not planned to bomb the Internet cafe, but that Raydi, reported to be 23, made a snap decision to detonate his bombs after the cafe owner caught him and Khouidri surfing terrorism web sites.

Raydi and Khouidri, reportedly 18 years old, were probably planning to carry out a criminal act later, Achour said, adding that police had not yet determined what the intended target was.

Raydi had been sentenced to five years in prison for involvement in Islamic terrorism, before being pardoned in 2005, according to the Interior Ministry.

Both Raydi and Khouidri were jobless and came from Douar Skouila, a poor neighborhood of Casablanca.