In the early hours of Dec. 20, a Hezbollah commander, along with several civilians, were killed by airstrikes in Damascus, calling up questions as to whether or not this was the result of opposition groups in Syria or another targeted assassination by Israel.

Samir Kuntar, 53, the commander who was killed, had a lot of enemies. A Lebanese citizen of the Druze religious minority, Kuntar dropped out of school at 14 to undergo armed training in the Palestinian refugee camps in Lebanon.

This would lead him, in 1976, to join the Palestinian Liberation Front (PLF)—a minor armed group that has variously joined and broken apart from several leftist Palestinian groups throughout the years.

Kuntar fought alongside the PLF for a few years, but his true notoriety came in April 1979, at the age of 16. He led a group of PLF operatives from Lebanon into Israel aboard a 55-horsepower motorized rubber dinghy with a max speed of about 55 miles per hour, landing at the coastal city of Nahariya.

The group began by killing the first police officer they encountered, and moved into the city to take hostages before Israeli security forces could respond. Kuntar and his gang found two members of the Haran family, father Danny, 31, and his 4-year-old daughter Einat in their home. Danny’s wife, Smadar, was hiding in a crawlspace with their 2-year-old daughter, Yael.

Quickly taken as hostages, Danny and his daughter were marched at gunpoint to the beach, and when the PLF militants found that their dinghy had been rendered unusable by gunfire, Kuntar shot Danny in the back, drowned him in the sea, and, according to the official Israeli account, bashed young Einat’s head with the butt of his rifle.

Two of the kidnappers were killed, while Kuntar and another PLF member were injured and apprehended in the subsequent clashes with Israeli police, and later put to trial in an Israeli court. They were found guilty of murdering five people—Danny, Einat, two policemen and 2-year-old Yael, who was accidentally smothered by her mother while she attempted to muffle her cries to remain unnoticed—and given five life sentences and an additional 47 years for injuries inflicted.

During his imprisonment, Kuntar became a boogeyman in Israeli society. The death of Danny and 4-year-old Einat inspired fear and disgust, and was widely discussed in media. Kuntar was Israel’s most reviled prisoner.

By 2008, Israel was prepared to let him go.

After years of tit-for-tat rocket launchings, cross-border raids and airstrikes following the end of Israel’s 18-year occupation of southern Lebanon in 2000, Hezbollah decided to hit Israel hard in July 2006. The Shia militia launched several rockets at targets in Israel’s northern Galilee region to distract the Israeli military while staging an incursion to capture Israeli soldiers on the Israel-Lebanon border.

It worked. Eight soldiers were killed, and two were captured. The kidnapping of these soldiers led to the full-on hostilities that lasted for 34 days and left 1,100 Lebanese, mostly civilians, and 150 Israelis, mainly soldiers, dead.

Two years later, a deal brokered by a United Nations-appointed German meditator saw Hezbollah returning the bodies of the captured soldiers in return for the release of Kuntar and four Hezbollah members captured during the war. It was a substantial victory, as Hezbollah leaders had previously stated that the release of Kuntar was one of their main motivations for taking the soldiers hostage.

At the time, the Israeli public strongly supported the exchange, but many still saw Kuntar as abhorrent. Then-spokesman for the Israeli prime minister Mark Regev told NBC News that Kutnar was “a brutal murderer of children and anybody celebrating him as a hero is trampling on basic human decency” in reference to the warm welcome he received in Beirut.

His freedom was short-lived.

Kuntar was killed on Sunday by missiles striking Damascus. Hezbollah claims they were fired by Israeli warplanes that were violating Syrian airspace. Is that true?

Probably. But it’s not the only possibility.

Following his return to Lebanon, Kuntar was ushered into Hezbollah’s high command. His location presence in the Syrian capital suggests he was active in Hezbollah’s efforts in the brutal civil war, which have deepened over the past year.

Hezbollah have recently increased recruiting efforts to bolster their forces in Syria, which are estimated at 3,000, about 15 percent of the group’s ground troops.

As the Syrian army has fallen apart after years of conflict, Iranian and Hezbollah fighters and commanders have taken the lead in efforts to keep Syrian dictator Bashar al-Assad in power.

Within the context of Syrian battlefields, these Shia operatives are universally hated by the Sunni, Salafist extremists that comprise ISIS, al-Qaeda affiliate Jabhat al-Nusra, and even many of the more “moderate” Islamist groups in the Free Syrian Army.

With the help of Russian airstrikes that began on Sept. 30, Shia fighters from Iran and Hezbollah, alongside the Syrian army, have retaken serious ground in recent months.

The Sunnis don’t like this, and that includes regional powers such as Saudi Arabia, Qatar, and Turkey, all of whom want Assad gone and the influence of Iran contained.

There were plenty of people who wanted Kuntar dead.

Still, it's most likely that it was an Israeli airstrike that took him out. It’s been a common move for the Israelis as the civil war intensified. One strike in January near the border of the occupied Golan Heights killed Jihad Mughaniyeh, the son of famed Shia militant mastermind Imad Mughaniyeh, along with four other high-level Hezbollah members.

This attack was followed by the bombing of an Israeli position in the Shebaa farms, the only part of Lebanon still occupied by Israel.

Regardless of who fired the missile, Sayed Hassan Nasrallah, the secretary-general of Hezbollah, has already made his decision: this was Israel. Now, the question is, how will Nasrallah respond to another high-level assassination?

Some think Hezbollah’s falling popularity with the Sunni majority in the Middle East due to its meddling in the Syrian conflict could use a boost, and a conflict with Israel would help.

Others say Hezbollah is stretched, and a war with the powerful Israeli military is the last thing the Shia group needs.

Either way, the world will know their response soon. Nasrallah and his backers in Iran aren’t likely to take this lying down.