TUNIS, (Reuters) – An explosion triggered by a fire ripped through an oil pipeline in the northern Tunisian city of Bizerte on Friday, prompting residents in at least one district to flee, residents and rescue service workers said.

Bizerte, a garrison town that houses Tunisia’s only oil refinery, is located 70 km (43 miles) from Tunis. The explosion hit the pipeline carrying oil to the STIR refinery terminal, the government said in a statement.

An initial fire caused the explosion, which sparked a bigger fire on the pipeline, the statement said.

“The exact causes behind the incident are still not known but work on the pipeline was under way before the incident occurred,” the government said, without giving details.

The fire and explosion caused material damage but no casualties, it added. Rescue workers, backed by government soldiers and refinery employees, brought the fire under control.

“The fire is now contained to one spot and the efforts were continuing to extinguish the flame,” the government added.

Residents near the facility were shaken by the blast.

“A huge explosion rocked the oil pipeline from the refinery to the port that feed ships docked there,” Zouheir Khelifi, who resides in the Intilaka neighbourhood some 600 meters (yards) from the pipeline, told Reuters.

“More than 200 families from our neighbourhood left home,” he added.

STIR, or Societe Tunisienne de l’industrie de raffinage, has a refining capacity of 30,000 barrels per day. The pipeline carries crude oil from southwestern Tunisia’s al Borma main oilfield. STIR, is majority-controlled state refiner.

Officials at the Energy Ministry, which controls STIR, were not immediately available to comment on the possible impact of the incident. STIR managers declined comment.