* Tripoli fighting spreads to western city district
* Benghazi calm after military base falls to militias
* EU pulls out staff, following U.S. and U.N. diplomats (Adds details from
Benghazi, EU evacuates staff)
By Patrick Markey
TRIPOLI, July 31 (Reuters) - Clashes with artillery and rockets spread on
Thursday into two Tripoli districts, where rival militia brigades were
battling over the airport in Libya's worst fighting since the 2011 revolt
that ousted Muammar Gaddafi.
Nearly 200 people have been killed since the violence erupted two weeks ago
in Tripoli and also in the eastern city of Benghazi, where a coalition of
Islamist militants and former rebels has overrun a major army base in the
city.
Three years after the fall of Gaddafi, Libya's fragile government and
nascent army have failed to impose authority on heavily armed brigades of
former rebels who have become the North African country's powerbrokers.
Fighting over two weeks has driven most Western diplomats out of the Libyan
capital, increasing international worries that the OPEC oil producer is
sliding toward becoming a failed state just across the Mediterranean from
mainland Europe.
Thuds of artillery, rockets and anti-aircraft cannons echoed across Tripoli
from early Thursday morning, a day after a temporary ceasefire agreed by
factions to allow firefighters to put out a huge blaze at a fuel depot hit
by a rocket.
There were no immediate reports of casualties from the new exchanges. But
the health ministry said on Thursday hospitals had reported 179 people
killed and more than 700 wounded in fighting in the two cities since the
start of violence.
Most of the fighting had been restricted to southern Tripoli where warring
factions have exchanged barrages between the airport controlled by Zintan
brigade fighters and enclaves allied to their Misrata brigade rivals.
Clashes with Grad rockets also broke out in the district of Seraj, Janzour,
17 km (10 miles) west of the capital, a Reuters reporter said. Local Janzour
brigades have usually been aligned against Zintan in the past standoffs.
Firefighters were still working on Thursday on dousing a massive fire
ignited at the fuel depot near Tripoli airport three days ago, the state-run
National Oil Corporation said, without giving details of how well the blaze
was under control.
Western governments hope the warring factions can reach some political
agreement within the newly elected parliament that is due to hold its first
session on Saturday in Tobruk, two parliamentary sources said.
BENGHAZI BATTLES
Once allies in the NATO-backed war against Gaddafi, the Misrata and Zintan
brigades have feuded in the past over control of parts of Tripoli since the
fall of the capital. But the recent fighting is the worst in three years.
Zintanis, from the western town of Zintan, have controlled the international
airport since Tripoli fell. Fighting has damaged the terminal and a control
centre and has burned commercial jets parked on the tarmac.
Clashes have also complicated the situation in Benghazi, after an alliance
of Islamist militants and former rebels overran a special forces base in the
city, forcing the army into a retreat, local residents and army officials
said.
Residents said there was little sign of army or police presence on the
ground in Benghazi on Thursday, two days after Islamist fighters from Ansar
al-Sharia and the coalition of former rebels, Benghazi Shura Council,
overtook the base.
The militant victory was an advance for Ansar al Sharia, classified as a
terrorist organisation by Washington. Ansar has been blamed by authorities
for an attack on the U.S. consulate in Benghazi in 2012 in which the U.S.
ambassador was killed.
Special forces have now joined up with air force units to back renegade
former army General Khalifa Haftar, a former Gaddafi ally who once lived in
exile in the United States and returned to fight with the rebels in the 2011
uprising.
Haftar launched a self-declared campaign against Islamist militants in
Benghazi, but in recent weeks appeared to struggle to make gains, residents
said. A twin suicide bombing last week showed how militants were
intensifying their response.
Haftar gained support initially from many residents tired of violence and
assassinations, but others rejected him as an old Gaddafi ally keen on
enhancing his own power.
On Thursday, a city police station and the military base were taken by
militants, and they were also holding western entrances to Benghazi,
residents and local officials said.
Hundreds of families have fled their homes after a week of clashes involving
warplanes and helicopter gunships.
Streets were almost empty and there was the smell of burning tires after
demonstrations against militia violence. But most of Benghazi was calm.
On Wednesday night, dozens of Benghazi protesters demonstrated in several
districts rejecting Ansar al-Sharia. One armed group clashed with militants,
and Ansar al-Sharia briefly left one of the local hospitals under its
control.
"Benghazi will not fall into the hands of these people," said Ali Salem, 27,
a local resident. "Even if the army did not succeed, then we will fight
them."
EU EVACUATIONS
The European Union said on Thursday it had evacuated international staff
from Tripoli because of the fighting.
"Following the deterioration of the security situation in Tripoli, the EU
has decided to temporarily relocate its international staff in Tripoli to
Tunisia," Michael Mann, spokesman for European Union foreign policy chief
Catherine Ashton, said in an e-mailed statement.
"Our colleagues have crossed the border with Tunisia this morning," he
added. He did not say how many staff were involved.
Thursday's decision by the EU follows similar steps by a majority of EU
member states, the United Nations mission and others with a diplomatic
presence in Tripoli, such as the United States and Turkey. (Additional
reporting by Martin Santa in Brussels; Editing by Mark Heinrich)