At least three people died and several were injured when heavy gunfire erupted during a demonstration at Beirut calling for the dismissal of a judge leading an investigation on the deadly explosion in the port of ' August 2020 . State news agency NNA reported three deaths in clashes in the Lebanese capital. An emergency doctor at the al-Sahel hospital in Beirut who did not want to be named sooner told CNN that the hospital had left one dead and nine injured since the violence began. Hundreds of supporters of Iran-backed Hezbollah and its main Shia ally, Amal, marched towards the city. Courthouse Thursday when shots were fired atprotesters from an unknown location, forcing protesters and journalists to take cover, according to a statement from the army and local broadcasters. There are several local reports of snipers shooting at protesters from rooftops of buildings in the area. Videos from local television and social media also showed masked protesters shooting what appeared to be AK-47s behind street barriers and rubbish tips, apparently retaliating at the gunmen, and black smoke billowing from one of the neighboring buildings. In a statement on Thursday, the Lebanese army, which was widely deployed at the scene of the shootings, said it would shoot any armed person in the areas where the clashes are taking place and called for people to leave the streets. Glass shards and debris are observed after gunshots erupted in the Lebanese capital on Thursday. Read more It is clear that those who shot at the demonstrators were organized armed groups that had been planning this attack since yesterday A senior Hezbollah official told CNN. We will not retaliate. They want to drag us into civil war and we don't want to sow civil war. In a joint statement released by Hezbollah and Amal, the groups called for calm among their supporters on the streets. Hezbollah has been a staunch opponent of Tariq Bitar, the popular judge who is leading the investigation into the Beirut explosion and has called for the prosecution of senior officials. This week the judge issued a warrant for his arrest. lawmaker Ali Hassan Khalil, a senior Amal official and former finance minister.