A Hamas official was killed Sunday when his sport-utility vehicle exploded in a Damascus neighborhood seconds after he started the engine, according to witnesses and the Palestinian militant group's leaders, who accused Israel of assassinating the operative.

"Our official position is we don't comment," said Gideon Meir, a senior Israeli Foreign Ministry official. He added: "Hamas immediately blames Israel because they are looking for an excuse to continue a campaign of terrorism against Israel and Jews. They will always blame us."

The Islamic Resistance Movement, as Hamas is formally known, confirmed the death of Izz El-Dine Khalil, 42, on its Web site Sunday and identified him as a spokesman for the group in Damascus, the Syrian capital. Khalil has been described as the leader of Hamas's military wing outside the Palestinian territories.

"This terrorist act represents a grave development that Israel shoulders responsibility for, as it emphasizes its intention to shake security and stability in the region," the Syrian state news agency said, quoting an official source.

The explosion occurred at 10:30 a.m. in the Az-Zahera neighborhood.

"He said good morning to us like he does every day and then walked to his car," a neighbor who identified himself only as Nabil told the Reuters news agency. "He got into the car, and then the [cell] phone rang. When he took the call, we heard the explosion. We rushed towards his car and found him in pieces in the back seat."

Israeli intelligence agencies have used telephones to detonate explosives in assassination efforts.

"Israel and Mossad are behind it," said Mushir Masri, a spokesman for Hamas in the Gaza Strip, referring to the Israeli intelligence service. "They assassinated him."

Israel drew international criticism a year ago when its fighter planes bombed a target inside Syria about 10 miles northwest of Damascus. Israeli officials said they were attacking a training camp allegedly used by several Palestinian groups. Israel has a long history of assassinating accused Palestinian militant leaders in foreign countries.

Earlier this year, Israeli security forces assassinated the top leaders of Hamas, including its spiritual leader, Sheik Ahmed Yassin, and his successor, Abdel Aziz Rantisi, in separate helicopter missile attacks in the Gaza Strip. Israeli officials frequently criticize the Syrian government for allowing Hamas to operate in its capital and have suggested they would hunt down officials of such groups outside the Palestinian territories.

On the day of Yassin's assassination, Prime Minister Ariel Sharon told the Israeli parliament: "The war against terror has not ended and will continue daily everywhere."

Hamas has conducted dozens of suicide bombings and other attacks against Israelis since the current phase of the Palestinian-Israeli conflict began four years ago. Israel has become especially aggressive in attacking members of Hamas since Sharon began pushing his proposal to evacuate Jewish settlements in the Gaza Strip, where Hamas is the most active and has the deepest social and political ties.

Special correspondent Islam Abdulkarim in Gaza City contributed to this report.