A senior Hezbollah commander was gunned down outside his home, the Lebanese Shiite group reported Wednesday, marking a further escalation in a shadowy series of attacks and bombings that risk drawing Lebanon deeper into the region’s simmering sectarian strife.

The militant Iranian-backed movement immediately blamed Israel for the assassination and warned that it would suffer the consequences. Israel denied that it was responsible.

But at a time when many in the region fear the consequences of warming ties between the West and Iran , and as Syria’s government gains ground against rebels with Hezbollah’s help, almost anyone could be responsible, analysts said.

“There are so many players around who could be involved in this,” said Elie Hindy, assistant professor for international affairs at Lebanon’s Notre Dame University. “Hezbollah has created so many enemies around it — regional enemies, Islamist enemies, Israeli enemies — and that does not include invisible possibilities.”

According to a brief statement issued by Hezbollah, veteran commander Hassan al-Laqees was shot late Tuesday in Hadath, a Christian-Shiite neighborhood six miles south of Beirut, as he returned from work near midnight. Lebanon’s Daily Star reported that he was shot five times in the head and neck in his car outside his home by at least one gunman.

“Israel automatically stands accused of responsibility,” the Hezbollah statement said, warning that Israel will bear “all consequences of this heinous crime.”

Although Israel usually does not comment on such allegations, the accusation brought a swift response.

“Israel has nothing to do with this incident,” Israeli Foreign Ministry spokesman Yigal Palmor told the Associated Press. “These automatic accusations are an innate reflex with Hezbollah. They don’t need evidence, they don’t need facts, they just blame anything on Israel.”

Hezbollah routinely blames Israel, with which it fought a brief but fierce border war in 2006, for attacks against its interests, and Israel has remained the chief suspect in the 2008 assassination of top Hezbollah commander Imad Mughniyah.

But many Lebanese said the killing of Laqees was more likely linked to the country’s soaring sectarian tensions , which have been aggravated by the war in neighboring Syria and a shift in the region’s balance of power in favor of Hezbollah’s sponsor, Iran.

“No one believes it was Israel,” said a Hezbollah supporter who lives in the Hezbollah-controlled southern suburbs of Beirut. The movement is accusing Israel “because it wants to avoid Sunni-
Shiite discord,” he said.

A previously unknown Sunni Islamist group calling itself Ahrar al-Sunna Baalbek Brigade asserted responsibility in a Twitter post , though neither its claim nor its existence could be verified. The group said it killed Laqees in retaliation for Hezbollah attacks on Sunnis in the eastern Bekaa region of Baalbek.

Hezbollah’s dispatch of fighters to support Syrian President Bashar al-Assad also has stirred resentment among Lebanese Sunnis, many of whom are increasingly falling under the influence of extremists. Bombings have targeted the southern suburbs, and suicide bombers attacked the Iranian Embassy last month .

Hours before the Hezbollah commander’s assassination, Lebanese television broadcast an interview in which Hezbollah chief Hasan Nasrallah accused Saudi Arabia of supporting Lebanese groups linked to al-Qaeda.

The attacks echo the bombings and assassinations that the group known as al-Qaeda in Iraq has carried out against Shiites to provoke civil strife in Iraq. But militants backed by the Syrian regime also have been caught conducting attacks in Lebanon, and a former government minister with close ties to Assad is awaiting trial on charges that he plotted bombings against Sunnis in Lebanon last year.

Although there are many possible suspects, the professionalism of the operation suggested “an intelligence service in the region which has an interest in escalating Shiite-Sunni tension,” said Hilal Khashan, professor of political science at the American University of Beirut.

Hezbollah, which has a controlling stake in Lebanon’s government and is the most powerful military force in the country, has no interest in risking its hold on Lebanon by retaliating, he added.

Ahmed Ramadan in Beirut and Ruth Eglash in Jerusalem contributed to this report.