Authorities say that at least one person has died and six others were hurt during a chain reaction crash in Fort Worth, Texas, this morning.

The crash was reported around 5 a.m. in the southbound lanes of I-35W near Seminary Drive, according to WBAP.

Authorities say that five passenger vehicles and one semi truck were involved in the pileup crash. The semi truck overturned on top of one of the cars during the collision, leaving a person trapped inside.

One person was killed in the crash. It isn’t clear if that person was in the semi truck or in one of the passenger vehicles. Six others were treated at the scene for various injuries.

All lanes of southbound I-35W are closed for cleanup of the crash. Fort Worth Police say that there is no estimated time for the reopening of the interstate. Delays have also been reported in the northbound lanes of the interstate because of drivers slowing to look at the aftermath of the crash.

The cause of the crash is still under investigation.