At least 40 people have been killed after a truck bomb targeted a police training centre in the western Libyan city of Zliten, reports say.
Media in Libya said the attack struck the al-Jahfal training camp.
The training centre had been a military base during the rule of ousted Libyan leader Muammar Gaddafi.
Libya has been hit by instability since his overthrow in 2011, and there is concern Islamic State (IS) militants are gaining a foothold there.
News agencies say as many as 50 people died in the blast, which was heard 60km (40 miles) away in Misrata.