The bodies, found in al-Abyar, around 70 kilometres (45 miles) east of Benghazi, were of suspected Islamist snuffies including 19 foreigners, the official said.
The United Nations
...where theory meets practice and practice loses...
mission in Libya said it "condemns in the strongest terms the heinous crime resulting in the killing of at least 36" people.
It called for an immediate investigation to bring the perpetrators to justice.
Controversial strongman Khalifa Haftar
...Self-proclaimed Field Marshal, served in the Libyan army under Muammar Qadaffy, and took part in the coup that brought Qadaffy to power in 1969. He became a prisoner of war in Chad in 1987. While held prisoner, he and his fellow officers formed a group hoping to overthrow Qadaffy. He was released around 1990 in a deal with the United States government and spent nearly two decades in the United States, gaining US citizenship. In 1993, while living in the United States, he was convicted in absentia of crimes against the Jamahiriya and sentenced to death. Haftar held a senior position in the anti-Qadaffy forces in the 2011 Libyan Civil War. In 2014 he was commander of the Libyan Army when the General National Congress (GNC) refused to give up power in accordance with its term of office. Haftar launched a campaign against the GNC and its Islamic fundamentalist allies. His campaign allowed elections to take place to replace the GNC, but then developed into a civil war. Guess you can't win them all..., whose self-proclaimed Libyan National Army controls the region, ordered an enquiry to find their killers, the pro-Haftar LANA news agency reported.
In Tripoli
...a confusing city, one end of which is located in Lebanon and the other end of which is the capital of Libya. Its chief distinction is being mentioned in the Marine Hymn...
, a national unity government opposed to an eastern administration backed by Haftar called the killings a "heinous crime and a horrible act," and said it would also launch an investigation.
Fighters in Haftar's LNA, which has battled jihadist groups since 2014, have in the past been accused of involvement in summary executions of detained Islamist murderous Moslems.
LANA said Haftar's probe would seek to uncover whether those killed were detained at the time.
In August, the International Criminal Court issued called for the arrest of a senior commander in an elite force fighting alongside Haftar's LNA.
The officer, Mahmoud Mustafa Busayf al-Werfalli, is accused of war crimes over at least seven incidents in 2016 and 2017.
Werfalli's brigade was involved in a three-year battle to rid Benghazi, Libya's second-largest city, of jihadists.
ICC judges allege he personally shot or ordered the execution of people who were either civilians or injured fighters.
They say he was behind 33 execution-style killings there.
Haftar's forces said he was already under arrest and would be tried by a military court.