Lebanon has heightened security presence throughout its main cities in response to increasing violence spilling across the border from Syria.

The Lebanese army has deployed extra troops and armoured tanks throughout Beirut and Tripoli after several people were killed during gunfights on 22 October. The fighting was between pro- and anti-Syrian groups.

The clashes followed the killing of Wissam al-Hassan, a top security official, on 19 October. Al-Hassan, who was the head of the intelligence branch of Lebanon’s Internal Security Forces, was killed in a bomb attack in the Ashrafiya area of Beirut. The attack killed three people in total and left more than 80 injured.

Lebanon’s President Michel Suleiman rejected an offer from Prime Minister Najib Mikati to resign following the assassination of Al-Hassan. Mikati currently leads the cabinet, predominantly made up of pro-Syrian Shia group Hezbollah and its allies. Al-Hassan had close ties with the opposition March 14 Coalition and headed the operation to arrest pro-Syrian politician Michel Samaha in August.

The president’s refusal to accept Mikati’s resignation has been criticised by several prominent politicians in Lebanon.

“The Lebanese people won’t accept, after today, the continuation of the government of assassination,” says Fouad Siniora, former prime minister.

Parliamentary sessions on 23 October were boycotted by opposition MPs in an effort to put increased pressure on Mikati.

The frequency and scale of violent attacks in Lebanon has increased steadily over the past six months as the civil conflict in Syria continues to worsen. The Syrian Observatory for Human Rights reports that more than 34,000 people have been killed in Syria since the conflict began in March 2011.

Fears that the Syrian civil war could turn into an intra-regional conflict have further increased after a Jordanian soldier was reportedly killed in a skirmish with Islamic militants moving across the Syria-Jordan border on 22 October.