BAALBEK, Lebanon (AP) -- A car bomb packed with explosives detonated near a Hezbollah base in eastern Lebanon Tuesday causing several casualties, officials said, the latest in a wave of deadly attacks that have targeted the Shiite militant group's interests in Lebanon.
However, there were conflicting reports on the source of the pre-dawn explosion and the number of casualties resulting from the blast in the remote, scarcely inhabited area was not immediately clear.
Hezbollah agents cleared the open field around the area and sealed it off for hours following the blast, making it difficult to establish what had happened.
Hours after the attack, at least four badly damaged vehicles, including the charred, twisted wreckage of an overturned jeep, lay strewn across the rocky field, where spots of blood mixed with patches of snow.
It was the first such attack against a Hezbollah outpost in eastern Lebanon's Bekaa region, following a spate of bombings that targeted Hezbollah strongholds south of the Lebanese capital.
Later Tuesday, three rockets hit just outside the northeastern region of Hermel, also a Hezbollah stronghold, without causing any damage, residents said.
The bombing appeared to be related to a series of reprisal attacks over Hezbollah's role in the civil war in neighboring Syria, where members of the group are fighting alongside President Bashar Assad's troops. It has received threats of retaliation from the largely Sunni rebels fighting to topple Assad, and Sunni extremist groups have claimed responsibility for bombings in the past few months that have killed dozens.
The Lebanese National News Agency said the perpetrator was a suicide bomber who detonated the vehicle near the village of Sbouba in the Baalbek region, about two kilometers (a mile) from a base belonging to the Iranian-backed group. The report said the explosion caused an unspecified number of casualties among Hezbollah members and civilians.
A Lebanese army statement and Hezbollah's Al-Manar TV station said the explosion was a car bomb, with Al-Manar saying the blast caused an unspecified number of casualties near a "rotation outpost" for Hezbollah fighters.
The station said a Hezbollah convoy of five cars was headed to the base when the group spotted a vehicle parked nearby and grew suspicious. They said several people were killed when they got out of their cars and the vehicle was detonated remotely.
Hezbollah has been instrumental in helping Assad's forces seize opposition-held areas in Syria, particularly in areas along the border with Lebanon and near Damascus.
The group's leader, Sheik Hassan Nasrallah, has vowed to continue fighting in Syria for as long as it takes to defeat what he says are "takfiris" -- radical Sunni groups -- who pose a threat to Lebanon.
Residents said the base referred to by Al-Manar may have been a logistical base for fighters traveling to and from Syria.
At the site of the explosion, Lebanese army investigators picked through the debris of the convoy that had been traveling in an otherwise deserted and muddy open field.
"I was still awake when I heard a very strong explosion," said a resident of the closest nearby village, Sbouba.
Hezbollah "removed the bodies of those killed before the army came in and took over," the villager said at the scene, speaking on condition of anonymity for fear of reprisals.
The NNA report said the car was "intercepted" by a Hezbollah checkpoint and exploded after members of the checkpoint fired on it.
A Lebanese security official could not confirm it was a suicide attack, however.
Hezbollah's participation in the civil war in Syria is highly divisive and unpopular in Lebanon, where many feel it has deviated from its original purpose of fighting Israel and that it has exposed the Shiite community to retaliation.
The group's open support of Assad has enraged Sunnis -- both in Syria and in Lebanon -- and left it with no shortage of enemies eager to strike at its strongholds and leadership.
Most recently, on Dec. 4, gunmen assassinated a senior Hezbollah commander, Hassan al-Laqis, in the garage of his building in a Hezbollah stronghold in southern Beirut.
Last month, two suicide bombers blew themselves up outside the Iranian Embassy in Beirut, killing 23 people. An al-Qaida-affiliated group claimed responsibility, saying it was payback for Hezbollah's support of Assad. At least two other car bombings have struck in the group's bastion of support, south of the capital, in the past few months.
The Syrian civil war has raised tensions in Lebanon's Sunni and Shiite communities as each side lines up in support of their brethren in the conflict next door. That has fueled predictions that Lebanon, still recovering from its 15-year civil war that ended in 1990, is on the brink of descending into full-blown sectarian violence.
In Tripoli, Lebanon's second-largest city, there have been bloody street battles between rival sides nearly every day, with at least 12 people killed in a particularly violent outbreak of fighting two weeks ago.
Karam reported from Beirut.
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