UPDATE: All lanes on I-75 South in Bradley County have reopened on Friday.

The southbound lanes were closed because of a crash near mile marker 21.

The cause of the crash is under investigation.

The condition of those involved is unknown at this time.

ORIGINAL STORY: A crash in Bradley County has shut down a portion of I-75 South on Friday evening.

It happened around 5:00 p.m. just north of Exit 20 around mile marker 21.

According to TDOT, all southbound lanes are closed in the area because of the crash.

The cause of the crash and the condition of those involved are unknown at this time.

TDOT expects to have the interstate reopened by 9:00 p.m.

Stay with the WRCB app for updates to this story.