A huge fire broke out Thursday at Beirut’s port, the site of last month’s catastrophic explosion that killed nearly 200 people, triggering panic among residents. It was not immediately clear what caused the fire at the facility, which was devastated by the explosion on 4 August, when nearly 2,750 tonnes of ammonium nitrate detonated. The blast triggered a shock wave that blew out windows, doors and walls miles away. A column of thick black smoke billowed from the port, with orange flames leaping from the ground. The firefighters and ambulances rushed to the scene. Army helicopters were taking part in efforts to extinguish the fire. There was speculation in Beirut that the fire could be an attempt to destroy evidence from the explosion last month that is blamed on government negligence and mismanagement. Panicked residents cracked open windows and called and texted each other to warn them of the new danger. Local TV stations said companies that have offices near the port asked employees to leave the area. Some hid in bathrooms, while others dropped what they were doing and rushed home. “We opened all windows and are in the corridor right now,” said Dana Awad, a mother of two girls in a Beirut neighborhood, recalling the tremor that preceded the earlier explosion. “I am still feeling the earth shake. Living a flashback.” French and Italian chemical experts working amid the remains of the port identified more than 20 containers of dangerous chemicals. The army later said these containers were moved and stored safely away from the port. Beirut Governor Marwan Abboud and authorities urged people to stay away from roads leading to the port to allow firefighters to move quickly. It was the second fire at the port this week. On Tuesday, a small fire also created some panic, but it was quickly extinguished.