The Libyan government vowed on Thursday to fight terrorism in its first acknowledgment that "terrorist groups" were behind dozens of attacks against security services and Westerners.

Three years after a revolution toppled longtime dictator Muammar Gaddafi and left the country awash with guns, near-daily attacks continue unchecked across Libya.

"The nation finds itself in a confrontation with terrorist groups, and it falls upon the government to mobilize its military and security forces to fight this scourge," the government said in a statement on its website.

"There will be no place for terrorism in Libya ... and Libyans must be prepared for such a battle in terms of caution, awareness and sacrifice," said the statement.

Eastern Libya has become a bastion for Islamist extremists, with authorities avoiding a full-blown confrontation with heavily armed former rebels pending the formation of a regular army and police force.

The government indicated it would turn to "the national military force as it is of now" in its fight against terrorism, alluding to pro-government militias that battled Gaddafi's regime in the 2011 uprising.

The statement was published after a Cabinet meeting was held in the southern town of Ghat, two days after a car bomb at a military academy in the restive eastern city of Benghazi left at least seven soldiers dead.

It also comes after National Congress ousted prime minister Ali Zeidan on Tuesday over his failure to bring law and order to the country.

The government said "the cities of Benghazi, Derna and Sirte and others are facing a terrorist war carried out by Libyan and foreign elements with hostile intentions."

Libyan authorities did not mention any particular group, but these cities are strongholds of extremists such as the jihadist group Ansar al-Sharia, which was placed on the United States' terror list in January.

While experts regularly accuse extremist groups of carrying out attacks, authorities have not directly implicated the heavily armed outfits out of fear of retaliation.

Ansar al-Sharia is suspected of waging attacks against judges and security forces, but also of being behind attacks on Western interests, such as an assault on the US mission in 2012 that killed the ambassador and three other US nationals.

The government statement called on "the international community and in particular the United Nations to provide the necessary support to eradicate terrorism in Libyan cities".