Some fighters for Libya Dawn shoot truck-mounted machine guns near the combat zone in Sabratha, Libya, on April 26, 2015. Clashes erupted on Sunday between the Islamist armed coalition Libya Dawn and pro-government forces near Wetia air base, some 170 kilometres west of the capital Tripoli. (Xinhua/Hamza Turkia)

A fighter for Libya Dawn is seen in Sabratha, Libya, on April 26, 2015. Clashes erupted on Sunday between the Islamist armed coalition Libya Dawn and pro-government forces near Wetia air base, some 170 kilometres west of the capital Tripoli. (Xinhua/Hamza Turkia)

Some fighters for Libya Dawn shoot truck-mounted machine guns near the combat zone in Sabratha, Libya, on April 26, 2015. Clashes erupted on Sunday between the Islamist armed coalition Libya Dawn and pro-government forces near Wetia air base, some 170 kilometres west of the capital Tripoli. (Xinhua/Hamza Turkia)

Some fighters for Libya Dawn shoot truck-mounted machine guns near the combat zone in Sabratha, Libya, on April 26, 2015. Clashes erupted on Sunday between the Islamist armed coalition Libya Dawn and pro-government forces near Wetia air base, some 170 kilometres west of the capital Tripoli. (Xinhua/Hamza Turkia)

Some fighters for Libya Dawn shoot truck-mounted machine guns near the combat zone in Sabratha, Libya, on April 26, 2015. Clashes erupted on Sunday between the Islamist armed coalition Libya Dawn and pro-government forces near Wetia air base, some 170 kilometres west of the capital Tripoli. (Xinhua/Hamza Turkia)

A fighter for Libya Dawn reconnoiters with a binocular near the combat zone in Sabratha, Libya, on April 26, 2015. Clashes erupted on Sunday between the Islamist armed coalition Libya Dawn and pro-government forces near Wetia air base, some 170 kilometres west of the capital Tripoli. (Xinhua/Hamza Turkia)