A massive fire has broken out at Beirut port on Thursday, a little more than a month since a huge blast devastated the port facilities and surrounding area.

The Washington Post's Beirut Bureau Chief Liz Sly tweeted that the Lebanese army has told people to evacuate the vicinity around the duty-free zone, and video is circulating on social media showing workers fleeing the area.

BEIRUT RESCUERS FRANTICALLY DIG THROUGH RUBBLE AFTER POSSIBLE HEARTBEAT DETECTED MONTH AFTER BLAST

Local TV stations said the companies that have offices near the port have asked their employees to leave the area and Lebanese troops closed the major road that passes near the port referring traffic to other areas, according to the Associated Press.

Although it was not immediately clear what caused the fire at the facility, the state-run National News Agency reported that the fire was at a warehouse where tires are placed.

Middle East Eye correspondent Ragip Soylu wrote on Twitter that the Lebanese Army confirmed a fire had broken out in a tire warehouse and that extinguishing operations -- including the use of army helicopters -- have already begun.

Soylu said authorities assured the fire would not lead to an explosion.

AJ English online correspondent Timour Azhari tweeted that there had also been "a smaller fire a couple [of] days ago that civil defense said they put out."

TIME's Rebecca Collard tweeted an ominous video showing a sky filled with dark smoke.

"Some of these [buildings] still don’t have windows after the #BeirutBlast a month ago and now they are being engulfed by (likely poisonous) black smoke," she wrote.

Police spokesman Col. Joseph Msalam told the Associated Press they have no information about what is happening at the port, adding that the facility is currently under control of the army.

When questioned about reports that the fire was caused by burning tires and oil, he said: “I don’t know. It could be containers. I really don’t know what is there.”

CLICK HERE FOR THE FOX NEWS APP 

The Aug. 4 explosion killed more than 190 people, injured around 6,500, and damaged thousands of buildings in the Lebanese capital after nearly 3,000 tons of ammonium nitrates detonated.

Last week, the military discovered more than 4 tons of ammonium nitrate near the port and said it was "dealing with the material."

This is a developing story, please check back for updates.