Hamas said Thursday that one of its operatives had been killed in the Syrian capital, and some officials of the militant group alleged that Israel was behind the slaying.

Israeli officials suggested, however, that the killing of Kamal Ghanaja was linked to the rift between Syria and Hamas over the group’s backing of the 15-month-old uprising against Syrian President Bashar al-Assad.

A prominent Syrian opposition group blamed the death on a ­Syrian pro-government militia.

Hamas officials said Ghanaja was killed in his home in the Qudsia neighborhood of Damascus by a group of assailants, who also seized files. His charred body, bearing marks of torture, was found Wednesday “in a ceiling closet, and a fire had engulfed the house,” said a source with ties to Hamas, according to the Reuters news service.

Hamas officials identified Ghanaja as a former deputy of Mahmoud al-Mabhouh, a senior Hamas operative who was assassinated in a hotel room in Dubai in 2010, a killing widely attributed to the Mossad, Israel’s foreign intelligence service.

Yisrael Hasson, a lawmaker and former deputy chief of the Shin Bet, Israel’s domestic intelligence agency, told Israel Radio that Ghanaja had “replaced Mabhouh, who was in fact responsible for supply of special weaponry to Hamas.”

A Hamas official told the French news service Agence France-Presse that “according to our information, Mossad was behind the assassination” of Ghanaja. He offered no evidence to support the claim.

Osama Hamdan, the top Hamas representative in Lebanon, said that “the only beneficiary of such an action is the Zionist occupier,” a reference to Israel.

But a Hamas statement in the Gaza Strip did not accuse Israel, saying only that an investigation had been launched “to identify the party behind this deplorable crime.”

The Local Coordination Committees, a prominent Syrian opposition group, said members of the pro-government militias known as the shabiha had tortured Ghanaja to death and “set his house on fire to destroy the evidence of their heinous crime.”

Asked about the allegations of Israeli involvement, Defense Minister Ehud Barak told Israel Radio, “I don’t think that is necessarily true.” In a separate interview with Army Radio, he added that “it is possible that not only Israel” was after Ghanaja.

Tensions between Hamas and Syria have grown in the past year since the group failed to support the Syrian government’s brutal response to the uprising in the country. Most senior Hamas officials who were based in Damascus, including the group’s leader, Khaled Meshal, have left, relocating to Qatar, Egypt and the Gaza Strip.

In February, the Hamas leader in Gaza, Ismail Haniyeh, saluted “the heroic people of Syria who are striving for freedom, democracy and reform,” signaling a break with Assad.