Lebanon caught up in the Syrian civil war Lebanon has once again suffered bloodshed on the streets of Beirut. The most powerful military force in the country, Hezbollah, was the target for the attack in the southern suburbs of the city. The area is a stronghold for the Shia Muslim militia and political movement, which has been backing troops loyal to President Bashar al-Assad. It is a reminder that the Syrian conflict is also having an effect on its neighbour. A Sunni Islamist group - calling itself the "Brigades of Aisha" has claimed responsibility for the massive car bomb. It gave a clear warning to Hezbollah leader Hassan Nasrallah that this was not the first attack or the last. A bombing in July in a nearby Beirut neighbourhood wounded 53 people. Despite supporting several uprisings during the Arab Spring, Nasrallah has chosen to back the al-Assad regime in Syria. Explaining his decision, the Hezbollah leader said that "it was after only after much thought that he decided to join the conflict in Syria." Hezbollah has been fighting alongside the Syrian army. They helped loyalist troops to retake the city of Al-Qusayr early in the summer as part of the effort to keep the Syrian regime in power. Syrian Free Army rebels have clearly identified their enemies. In a video posted on the internet in June, they showed the identify papers of four Lebanese nationals killed as they attempted to enter Syria. However, the rebels deny they are behind the attacks on Lebanese soil. For several months now tension has been high with almost daily clashes in Lebanon between Sunni Islamist groups. They say their enemies are the Syrian regime and Hezbollah, as well as the Lebanese army. But overshadowing these attacks against Hezbollah - linked to its support to Assad - is the presence of Israel, which is key to political alliances in Lebanon. Israel is particularly focused on the Shia group, as Hezbollah is a close ally of Iran. Israel has also been accused of involvement in the attacks, an allegation it strongly denies. More about: Attack, Hezbollah, Lebanon, Syria