At least 50 people were killed on Thursday when a truck bomb exploded outside a police training centre in the western Libyan city of Zliten.
The attacker struck the al-Jahfal training camp, BBC reported. The centre was a military base during the rule of ousted Libyan leader Muammar Gaddafi.
The UN Special Representative to Libya, Martin Kobler, said the blast was a suicide attack.
Hundreds of recruits were outside performing morning exercises when the deafening explosion took place. Libya's al-Naba television network said a state of emergency had been declared.