Convicted murderer Samir Kuntar, who was released in a prisoner exchange deal with Hezbollah three years ago, was reportedly wounded in an explosion in southern Beirut on Friday. Kuntar, a Druze Lebanese who was active in the Palestinian Liberation Front, was known for his role in a 1979 attack in the northern Israeli town of Nahariya in which three members of the Haran family, including two young girls, and an Israeli policeman were killed. According to the German Press Agency DPA, the blast occurred Friday night in an apartment on the 10th floor of a building in the Roueiss neighborhood of Beirut, considered a Hezbollah stronghold. Reports said one person was killed and five more, including Kuntar, were wounded. Hezbollah is still locking down the blast area in Dahiyehs Rouweis and is not allowing the Lebanese security forces to enter the apartment in which the explosion took place, Lebanese television reported on Saturday. The Lebanese daily newspapers An Nahar and Al-Liwaa said that a small bomb or a hand grenade could have been the cause of the blast, which triggered a huge fire at an apartment building in Roueiss. There was no official comment by Hezbollah on the blast, but a Lebanese security source told DPA that Hezbollah gunmen fired in the air to disperse curious onlookers and prevented Lebanese police investigators from reaching the area to investigate the incident. In 1979, Kuntar and others attempted to abduct the Haran family in Nahariya, an attempt that turned into a gun battle with Israeli security forces. Kuntar shot and killed the father, Danny Haran, 31, and used his rifle butt to bludgeon the head of Harans daughter, Einat, 4. He also killed an Israeli policeman, Eliyahu Shahar. Harans younger daughter, Yael, 2, was suffocated when her mother tried to keep her quiet while they hid from the terrorists. Kuntar was convicted of three counts of murder and one of indirectly causing the death of Yael Haran. After serving three decades in an Israeli prison, Kuntar was returned to Lebanon as part of a 2008 prisoner swap between Israel and Hezbollah. In return, Israel received the bodies of reserve soldiers Ehud Goldwasser and Eldad Regev, who had been abducted and killed during the Second Lebanon War in 2006. Kuntar's condition following Friday's blast was unclear. Some media outlets reported him dead while others said he was injured. No official confirmation has been released. Senior Hezbollah officials acknowledged in Hezbollah-aligned media on Saturday that there had been an explosion in an apartment and that some people had sustained injuries. The An Nahar daily reported that the blast, apparently caused by a hand grenade or explosive device, occurred on the 10th floor in a building in the Dahiyeh quarter where Kuntar lives. The apartment is also located near a mosque where Hezbollah leader Hassan Nasrallah frequently gives speeches and Hezbollah members hold meetings. Hezbollah has so far refrained from assigning blame to foreign countries such as the U.S. and Israel, instead labelling the explosion a work accident. A senior Hezbollah official vehemently denied that the apartment served as an ammunition depot but refused to comment on whether Kuntar had been injured.