BEIRUT (REUTERS) - The death toll from a car bomb which ripped through the southern Beirut stronghold of Lebanon's militant group Hezbollah rose on Friday to 24, and the government said it was investigating whether the blast was a suicide attack.
Interior Minister Marwan Charbel said investigators were checking CCTV footage in the moments before the explosion to see whether the van which was believed to be carrying the bomb had been driven by a suicide bomber or detonated remotely.
"The first hypothesis is that the driver blew himself up, while the second hypothesis says that the car may have been blown up from a distance," Lebanon's National News Agency quoted Mr Charbel as saying.
Reporters who arrived at the scene minutes after the explosion saw a burnt-out car near the centre of the road, suggesting it was being driven when it blew up.
Hezbollah parliamentarian Ali Ammar told reporters in south Beirut on Friday that the death toll had reached 24, while Health Minister Ali Hassan Khalil said 21 bodies were taken to hospitals and another 335 wounded people had been treated.
The discrepancy in death tolls may be the result of some bodies being too badly damaged in the explosion to be collected or identified.
Among the dead were a family of five - a father, mother and their three daughters - who were killed in their car by the blast, which destroyed several vehicles and briefly engulfed the lower floors of adjacent building in flames, trapping residents.
The blast, a month after another car bomb wounded more than 50 people in the same district of the Lebanese capital, came amid sectarian tensions over the intervention of Shi'ite Muslim Hezbollah against Sunni rebels in Syria's civil war.
A Sunni Islamist group calling itself the Brigades of Aisha claimed responsibility for the attack and promised more operations against Hezbollah.
Residents of southern Beirut say Hezbollah, backed by Iran and Syria, had been on high alert and stepped up security in the area after warnings from Syrian rebels of possible retaliation for the group's support for President Bashar al-Assad.
Hezbollah leader Sayyed Hassan Nasrallah is expected to give his response later on Friday in an address marking the seventh anniversary of the end of Hezbollah's 2006 war with Israel.
Many Lebanese politicians pointed the blame at Israel in the immediate aftermath of the explosion, but Israeli President Shimon Peres said Lebanon should look elsewhere for the culprit.
"I was surprised," he told a joint news conference with United Nations Secretary-General Ban Ki-moon. "Why should (they) look to Israel? (They have) a Hezbollah that collects bombs, that goes and kills people in Syria without the permission of the Lebanese government."