TEHRAN -- Five people were killed, and five others injured on Saturday in a six-vehicle chain-reaction pileup in the western Iranian province of Ilam, the official news agency IRNA reported.

The accident, involving collisions among three semi-trailer trucks and three sedans, occurred on a road from the provincial capital Ilam to Mehran County, IRNA quoted Hamzeh Mohammadi-Moqaddam, head of the province's Red Crescent Society, as saying.

The incident was reported to the society's emergency operations center at 10:05 a.m. local time (0635 GMT), he said, adding that 13 operational rescue teams were immediately sent to the scene, and the injured had been transferred to medical centers.

Ilam's Traffic Police Chief Abolfazl Kahzadi said a technical malfunction in the brake system of one of the semi-trailer trucks had caused the collisions, according to the Iranian Students' News Agency.