At least 36 people were killed during the weekend's clashes between Libyan Special Forces and Islamist militants in Benghazi, security officials said.
The government said more than 150 people have died, many of them civilian, in the capital Tripoli and Benghazi in two weeks of fighting as clashes forced UK and other foreign diplomats to pull out of the country.
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David Browning admits manslaughter by diminished responsibility but denies murder.