SOFIA: Bulgarian authorities are investigating the apparent shooting death on Friday of a Palestinian, wanted by Israel for a 1986 killing, inside the Palestinian Authority's embassy in Sofia.

The embassy identified the dead man as Omar Nayef Zayed, who took refuge in the embassy late last year fearing extradition to Israel.

The Bulgarian prosecutor's office said it was told by the embassy Friday morning of a death resulting from violence on the territory of the embassy. The Palestinian ambassador granted access to the investigators, it said, adding that the cause of death has not been established yet.

The Palestinian militant group PFLP, however, reported Zayed was shot in the head.

Zayed (52) escaped from Israeli custody 25 years ago and has lived in Sofia since 1994. He was convicted of the murder of an Israeli man in Jerusalem's Old City and given a life sentence.

The official Palestinian news agency WAFA said Palestinian President Mahmoud Abbas has ordered an investigation committee to go to Bulgaria immediately and probe the circumstances of the killing. Abbas was quoted as condemning the killing.

PFLP said Zayed was a member of their organisation, who together with his brother and another Palestinian had stabbed an Israeli in 1986 and had received life sentence.

In 1990, Zayed was hospitalized in Bethlehem following a hunger strike, and later escaped from the hospital, moving to several Arab countries before settling in Bulgaria.

Israel asked the Bulgarian justice minister in 2015 to extradite him and Bulgarian authorities called on him to surrender. He refused and sought refuge in the Palestinian Authority's embassy in Sofia.

His brother, Ahmed Zayed, and the other Palestinian were among those released in a 2011 swap for an Israeli soldier, Gilad Schalit, who had been held by Hamas-allied militants in Gaza for five years.