Fighters allied with Libya's UN-backed unity government have captured two coastal towns from the Islamic State group in an advance towards its bastion Sirte, a spokesman said on Tuesday.

The Petroleum Facilities Guard overran Ben Jawad and Nofiliya as they thrust westwards along the Mediterranean coast from their base in Libya's eastern oil ports, the spokesman for the force said.
Five people were killed and 18 wounded in Monday's fighting, sector commander Colonel Bashir Buthefira said.
"Our forces have taken control of Nofiliya and are now advancing towards Harawa" about 75 kilometres (45 miles) east of Sirte, he said on Tuesday.
Sirte was the home town of slain dictator Moamer Kadhafi and, since seizing it in June last year, IS has turned it into a recruitment and training camp.
Western governments fear the jihadists could use Sirte's port and airport as a springboard for attacks in Europe.
But they have called for any offensive against the IS stronghold to be carried out under the auspices of the unity government installed in Tripoli since March 30 for fear that rival operations could play into the jihadists' hands.
The unity government has gradually asserted its control over key state institutions, but it still faces a rival administration with its own army in the east.
Both sides are pushing towards Sirte, prompting the UN's special envoy on Libya to call on all armed groups to unite against IS.
"The fight against Daesh, which is the number one enemy, must be a Libyan fight and a united fight," said Martin Kobler, using an Arabic acronym for IS.
The rival administrations should "unite their efforts" into a single army, he said in Paris after meeting French Foreign Minister Jean-Marc Ayrault.