An assortment of armed forces have confronted the Islamic State in Libya since the jihadist group made inroads in the conflict-wracked country in 2014.
The following is a rundown:
– Recognised government forces –
Controversial retired General Khalifa Haftar commands the military of the Libyan government that has taken shelter in the far east of the country and which is recognised by the international community.
The Libyan army, whose land forces are supported by MiG-21 and MiG-23 warplanes, in 2014 evicted Islamists from much of the country's second city of Benghazi, 1,000 kilometres (600 miles) east of the capital Tripoli.
In February, the loyalists also retook the Mediterranean city's jihadist stronghold of Lithi, a district called the "Kandahar of Benghazi" after the hotspot in Afghanistan.
– Fajr Libya (Libya Dawn) –
A motley grouping of militias, mainly Islamists, which fought against Libyan leader Moamer Kadhafi's forces in the 2011 revolution and emerged as one of the North African country's most heavily armed fighting forces.
Its core is made up of groups from the city of Misrata, 200 kilometres east of Tripoli.
Fajr Libya seized control of the capital in August 2014, expelling rival militiamen from the town of Zintan, southwest of Tripoli.
It has since, in effect, become the armed wing of a rival administration based in the capital.
Fajr Libya controls virtually all coastal cities between Misrata and the Tunisian border as well as southern towns such as Gharyan, Nalut and Jado in the mainly Berber mountain range of Nafusa.
The alliance includes moderate Islamists and members of the Berber minority, and Fajr Libya also has a presence in the south's main city of Sabha.
Military units of the Tripoli-based government battled IS last year in the eastern city of Sirte where the jihadists had made advances, only to be repelled, leaving IS in control of the whole of the city and of surrounding areas.
Last month, Fajr Libya mounted a lightning assault to expel IS which had briefly taken over the centre of Sabratha, a coastal city 70 kilometres west of Tripoli.
– Cyrenaica Force –
The Cyrenaica Force is an anti-Islamist coalition of local tribes in eastern Libya led by Ibrahim al-Jodrane. It backs a federal government and demands autonomy for the region. Its forces blocked oil terminals in the east for a year, bringing Libya's crude exports to a halt.
The group has not clearly backed Haftar despite its hostility to Fajr Libya.
In January, it fought against IS forces and aborted their bid to take control of oil installations in the region known as Libya's "oil crescent".
– Revolutionary Shura Council of Derna –
The Council is a mix of militias including Islamists that now controls Derna. The city, 1,100 kilometres east of Tripoli, was an IS stronghold before they were driven out in July 2015.
The jihadists have since taken up positions on the edges of Derna and mounted attacks on fighters of the Shura Council.