An Israeli court has convicted two minors for burning a Palestinian teenager to death in a revenge attack but held up the verdict for the main alleged assailant, sparking protests. The three-judge panel in Jerusalem found two Israeli youths, who have not been named, guilty of kidnapping 16-year-old Mohammed Abu Khdeir, beating him unconscious and then killing him by dousing flammable material on his body and setting it on fire in July 2014. Sentencing is expected in early 2016.

The court however postponed its ruling over the fate of the suspected ringleader, 31-year-old Yosef Haim Ben David, after his defence filed a last minute insanity disorder plea. Judges acknowledged the defendant committed the crimes he is charged with but said they could not convict him, pending psychiatric evaluation.

The move infuriated relatives of the victim and Israeli Arabs who saw it as evidence of double standards in the country's legal system. "This crime cannot wait in court for a year and a half and two days before resulting in an opinion that he's insane," said Abu Khdeir's father, Hussein, Ynet reported. "I'm afraid the court will acquit him".

"I am afraid of more Ben Davids appearing if the court doesn't deter them. I want their houses to be demolished," he added, referring to the Israel's controversial practice of destroying the homes of Palestinians involved in attacks against Israelis.

A few hundred people protested outside court after the verdict was read out. "Muhammad Abu Khdeir was murdered only because he was an Arab, and this time, like many times in the past, when the murderers are Jews, the legal system protects them," Ayman Odeh, the leader of the Joint List Arab political alliance, told the Jerusalem Post.

Another Arab, Joseph Jabarin, said it was "unthinkable" Ben David could escape immediate sentencing. "The Palestinian public already does not have faith in the Israeli justice system and this decision only strengthens that belief," he was quoted as saying by the Israeli newspaper.

Abu Khdeir's slaying was in retaliation for the killing of three Israeli teens in the West Bank last summer. The murders set off a wave of violence that peaked with a 50-day conflict in Gaza. The verdict in Abu Khdeir's case came at a sensitive time as it risks fuelling tensions that are again running high amid a spate of attacks that has engulfed the region over the past two months.