Hezbollah chief blames radical Islamists for Beirut bomb
The leader of Lebanon's militant Hezbollah group, Hassan Nasrallah, has said extremist Islamists bombed a Beirut suburb, killing 22 people.
Sheikh Nasrallah said "takfiris" - militants who believe Muslim society has reverted to a state of non-belief - were likely to have been responsible.
A previously unknown group calling itself the Battalions of Ayesha said it carried out Thursday's bombing.
The attack took place in a Shia area known to be a stronghold of Hezbollah.
Sheikh Nasrallah urged his followers not to react blindly to the bombing which, he said, was aimed at drawing Lebanon into Syria's conflict.
He said if the attackers' aim had been to deter Hezbollah from fighting alongside the regime in Syria, his movement would double its forces there.
Sheikh Nasrallah said he would "go myself to Syria if it is necessary in the battle against the takfiris".
Hezbollah supports the government of Syrian President Bashar al- Assad in the civil war.
The site of the blast is close to the Sayyed al-Shuhada complex, where Hezbollah often holds mass rallies. Hundreds of people were injured in the attack.
Interior Minister Marwan Charbel said officials were investigating if the van believed to be carrying the explosives had been driven by a suicide bomber.
The explosion comes a month after another car bomb wounded more than 50 people in the same district of Beirut.
Fighters from Hezbollah were instrumental in a strategic victory by Syrian government forces in Qusair, close to the border with Lebanon, in early June.
In a video message posted online, the Battalions of Ayesha suggested they had been behind July's bomb blast. The group threatened to carry out more attacks, referring to Hezbollah strongholds as "colonies of Iran".
Events in Syria are putting Lebanon's fragile peace in jeopardy, threatening the equilibrium which has held since the end of the civil war more than 20 years ago.
Many Lebanese politicians blamed Israel in the wake of Thursday's blast, but Israeli President Shimon Peres denied culpability during a joint news conference with United Nations Secretary-General Ban Ki-moon.
"I was surprised," Mr Peres said. "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."
Correction 23 August 2013: This story has been amended to make clear that Hassan Nasrallah did not directly accuse Sunni radicals of being behind the attack.