Ramallah, West Bank - Almost a week after he was found dead in the Palestinian embassy in Bulgaria, Omar Nayef Zayed's case continues to grip the occupied Palestinian territories.

On Tuesday, a few dozen Palestinians protested outside the Bulgarian Representative office in Ramallah amid a heavy security presence.

The protesters held a banner threatening that "the crime of assassinating Al Nayef (Zayed) won't go unpunished", raising posters of the 51-year-old found in a pool of blood outside the building in Sofia.

The protesters held the Bulgarian authorities responsible and demanded the truth about his death be revealed.

"We came here to deliver a clear message to the Bulgarian representative; that they are responsible for this heinous crime," Ahmad Zayed, Omar's brother told Al Jazeera.

"They should have provided protection for Omar and the Palestinian embassy, but they didn't."

An ambulance leaves the compound of the Palestinian embassy in Sofia [Stoyan Nenov/Reuters]

A Palestinian native from the West Bank city of Jenin, Zayed was sentenced by an Israeli court to life in prison after being charged with killing a yeshiva student in occupied East Jerusalem in 1986.

Four years into his sentence, he managed to escape Israeli custody during a hospital visit. He ended up in Sofia in 1994, and was granted residency, starting a family.

Zayed's quiet life running a grocery store with his wife and three children turned upside down a couple of months ago, when the Israeli embassy in Sofia requested that the Bulgarian government extradite him on December 15.

He sought refuge in the Palestinian embassy only to be found covered in a pool of his blood last Friday.

His family, the Popular Front for the Liberation of Palestine (PFLP) of which Zayed was a member, as well as other factions and several Palestinian officials have all pinned his death on Israel.

"It is only natural to accuse Israel as being the number one culprit in this crime. If there were no occupation, there would not be this situation," Ahmad al-Madbouh, the Palestinian ambassador to Bulgaria said.

Issa Qaraqe, the head of the Palestinian Commission for Prisoners Affairs, said he believed the Israeli security forces were behind the attack.

Israeli denial

Other Palestinian prisoners' support groups warned of the gravity of the assassination on the fate of released prisoners.

Israel has distanced itself from the allegations saying that it would not get entangled with an assassination after filing an official request for extradition, and not while the Bulgarian prime minister was visiting the country on a work trip.

An Israeli foreign minister spokesman said that it was not an Israeli issue, but would not comment further.

Neither Zayed's family, nor the PFLP, spared the Palestinian Authority from blame. Besides failing to save his life, they claim Omar was under pressure from within the Palestinian embassy to leave its premises.

At the embassy, they used to tell him Israel has all the keys, Omar's wife, Rania, told Al Jazeera in a recent interview.

"Although you're in the embassy, we can't protect you. They used to threaten him to leave the embassy," she said.

Several versions about what could have happened on Thursday or Friday remain uncertain and somewhat contradictory.

The place, status and circumstances in which the body was found have raised lots of questions. It is unclear whether he committed suicide or was pushed by someone.

No information has been made available on how long his body lay there before discovery, or whether Zayed had died somewhere else and his body moved to the scene later.

Zayed's family and supporters have pointed to the fact that no surveillance cameras were placed inside the building despite its political sensitivity.

Investigation committee

Palestinian President Mahmoud Abbas formed an investigation committee that includes the deputy Palestinian foreign minister, a security official and a PLO representative. The committee, which Zayed's eldest brother joined later, arrived to Bulgaria on Sunday.

"We're waiting for developments, but we fear that there is a conflict of interest because a member of the committee is a representative of the Palestinian Foreign Ministry," Ahmad Zayed said.

The Bulgarian authorities have made their position clear: there will be no joint investigation between Bulgaria and the Palestinian delegation, because it does not consist of prosecutors and investigators, the Bulgarian Prosecutor-General reportedly said on Tuesday.

If they want information, they could get it via the Bulgarian Foreign Ministry, he added.

Autopsy results are expected to be released within the next two days and Bulgarian prosecutors are questioning witnesses and Omar's family trying to seek answers.

Source: Al Jazeera