The terrorist group affiliated to Syria’s al-Nusra Front claimed on Twitter that the Saturday attack, which targeted a petrol station in Hermel in eastern Lebanon, was a suicide bombing in response to Hezbollah's Syria policy.

"At least four people were killed and more than 15 wounded, two or three of them in critical condition," Marwan Charbel, Lebanon's interior minister, told Hezbollah's al-Manar television station.

The petrol station is part of a charitable network set up by late Ayatollah Mohammed Hussein Fadlallah, a leading Shia religious leader and Hezbollah spiritual guide who died in 2010.

It was the seventh attack to target Hezbollah in Lebanon since mid-2013. Saturday's blast was the second terrorist attack in less than a month to hit Hermel, close to the border with Syria.

The Hermel explosion occurred at around 16:00 GMT after dusk on Saturday near a school run by a charity group for impoverished children, some of them orphans.

An official speaking on al-Manar said no children were injured.

Security forces later closed off the area and fire-fighters managed to extinguish the blaze.

Al-Nusra Front in Lebanon had previously claimed another attack five days earlier in the Hezbollah-dominated southern suburbs of Beirut.

Lebanon's caretaker Prime Minister Najib Mikati condemned the bombing as a "terrorist attack", and called for unity to "protect our homeland".

Omran al-Zoabi, Syria's information minister, speaking on Lebanon's al-Mayadeen TV, said "this terrorist attack, like those before it, only benefits the Israeli enemy".

NTJ/HH