JACKSBORO, Tenn. (AP) -- Tennessee transportation officials are closing both southbound lanes of Interstate 75 just below the Kentucky state line.

A rock slide had caused the closing of one northbound and one southbound lane on Thursday. Tennessee Department of Transportation geotechnical engineers have since determined that an earthen embankment under the highway is sliding near the Stinking Creek exit at mile marker 144.

The closure will force thousands of southbound drivers to take a 26-mile detour through LaFollette to get around the site. It is expected to affect college students heading south for spring break.

TDOT planned to close the southbound lanes at 2 p.m. EST on Friday. There was no estimate about when the section might reopen.

TDOT spokesman Mark Nagi said southbound traffic on I-75 should take the Jellico exit at mile marker 160 and detour to exit 141 at Caryville.