The California Highway Patrol (CHP) is investigating after a semi truck drove the wrong way on a major interstate over the weekend.

On Sunday, June 15, multiple 911 callers reported a wrong-way semi truck on I-5 in Siskiyou County, according to CHP’s Yreka division.

Callers told police that the truck drove through the center median and then went north in the southbound lanes of I-5.

“One of our officers was able to get into position and intercepted the big rig before a tragedy occurred. This was a very unique and dangerous situation,” CHP said.

Drugs and alcohol were not a factor, according to police.

“Thank you to all the concerned citizens who reported this incident so we could take appropriate action! Your quick thinking might have saved lives,” said CHP.

The incident remains under investigation.