Initial autopsy results from the body of Mohammad Abu Khudair, 16, who Palestinians believe was kidnapped and killed by far-right Jews, showed that "the direct cause of death was burns as a result of fire and it's complications", said Palestinian attorney-general Mohammed Al-A'wewy.
Israeli-Palestinian tensions have risen sharply after three Israeli teenagers were kidnapped on June 12. The bodies of Naftali Frenkel and Gilad Shaar, both aged 16, and 19-year-old Eyal Yifrach were found on Monday.
This was followed on Wednesday by the kidnapping of the Palestinian youth in his neighbourhood in Arab East Jerusalem. His charred body was found hours later in a forest on the edge of the city.
Saber Al-Aloul, the director of the Palestinian forensic institute, attended the autopsy which was carried out by Israeli doctors in Tel Aviv.
Al-A'wewy said Al-Aloul had reported that fire dust material was found in Abu Khudair's respiratory canal which meant "the boy had inhaled this material while he was burnt alive."
Burns covered 90% of the surface of the teenager's body and his head had been cut. Samples such as liquids and tissue were taken for more lab examinations to complete the legal medical report.
At Abu Khudair's funeral on Friday, furious Palestinians chanted "Intifada! Intifada!", calling for a new uprising against Israel. Stones thrown at Israeli police were met by teargas, stun grenades and rubber bullets in one of the most highly charged displays of enmity in Jerusalem in years.
Clashes continued across the occupied West Bank yesterday, with at least one Palestinian hurt in the city of Nablus, while clashes also erupted in Israeli-Arab towns.
Israeli newspaper Haaretz reported that some 50 Palestinians and 13 policemen were hurt in clashes, which it said had spread to all of East Jerusalem's districts.
It quoted Foreign Minister Avigdor Lieberman as saying that rioters "do not belong in the state of Israel - and until that is resolved, their place is in jail".
Meanwhile, in southern Israel, rockets and mortar shells fired from the Gaza Strip continued to fall in and around nearby towns.
The Israel Defence Forces returned fire, striking several targets within the Strip.
Palestinian officials trying to calm tensions have said they would prevent any intifada - uprising - and seek a solution to the crisis.
Within the Palestinian community many people, including President Mahmoud Abbas, assert that Abu Khudair was the victim of Jews incensed at the Israeli deaths.
Israeli Prime Minister Benjamin Netanyahu called Abu Khudair's killing, one day after the three Jewish seminary students were buried, "loathsome" and ordered a swift police investigation.
Israeli authorities said they did not yet know whether Abu Khudair was indeed the victim of a hate crime.
With Israel having mobilised ground forces outside Gaza on Thursday in a threat to invade, Egypt has intensified efforts to mediate a truce.
Meanwhile, Israel and the Islamist Palestinian Hamas movement remain in a stand-off, with each saying the other had to back down first.