RAMALLAH, West Bank - A Palestinian official died Wednesday after a clash with Israeli soldiers in the West Bank, Palestinian officials reported.

Ziad Abu Ein, 55, headed the Palestinian Authority's Committee against the Separation Wall and Settlements. According to initial Palestinian reports, he died after inhaling tear gas and being struck in the chest by an Israeli soldier during a confrontation between Israeli troops and Palestinians who were planting olive trees in the village of Turmus Ayya, north of Ramallah.

Abu Ein was taken in critical condition to the Palestine Medical Complex in Ramallah, where he died soon after, Palestinian officials said.

According to the medical center's director, Ahmad Beitawi, Abu Ein was initially believed to have suffered a heart attack after the confrontation.

Beitawi told reporters that an autopsy would be performed but that he could confirm the cause of death was "inhaling tear gas, which caused problems in the heart and lungs." Beitawi said the tear gas that entered Abu Ein's lungs induced vomiting and suffocated him.

A Reuters photographer who witnessed the incident said Abu Ein was struck by a hand to the neck.

Fatah Central Committee member Mahmoud Aloul told Palestinian radio that Abu Ein collapsed after inhaling tear gas fired directly at him. "We thought his injury was light, but were shocked when we heard he died," Aloul said.

Palestinian Authority Chairman Mahmoud Abbas condemned Abu Ein's death as a "barbaric act that we cannot remain quiet about or accept."

In a statement carried by the official Palestinian news agency WAFA, Abbas declared three days of mourning through areas controlled by the Palestinian Authority and said he would take "all necessary measures" when the investigation of the incident was concluded.

The Palestinian leadership was scheduled to convene Wednesday evening to discuss the situation. Reports that Palestinian officials planned to suspend security coordination with Israel were not confirmed.