BEIRUT — A huge fire erupted in a truck at a border crossing between Syria and Jordan on Thursday, Syrian opposition activists said. There was no immediate information about what caused the blaze or whether there were any casualties.

According to activists, the truck was carrying flammable paints.

The Nassib border crossing with Jordan was reopened in 2018, months after it fell under Syrian government control. Syrian rebels had seized the crossing in 2015, severing a lifeline for the government in Damascus and disrupting a major trade route linking Syria and Jordan, Lebanon and the oil-rich Gulf countries.

The Britain-based Syrian Observatory for Human Rights, an opposition war monitoring group with activists on the ground, and Daraa 24, an activist collective, said thick black billowed from the area.

The Observatory's chief Rami Abdurrahman said the blaze might have been an accident and was apparently not caused by explosives.

Syrian state media did not report on the incident and there was no immediate word from Jordan.