Update at 7 p.m.: The wrecks have been cleared and traffic is flowing normally.
Update at 5:45 p.m.: Traffic on I-75 is backed up for miles, as far south as Exit 345 at Ringgold/Tunnel Hill. Most traffic is stopped or very slow.
Update at 5:30 p.m.: Chattanooga police say the wreck on I-75 has been cleared and the accident on I-24 is almost cleaned up.
Traffic is now moving, but two wrecks blocked traffic this afternoon on interstates in the Chattanooga area.
A tractor-trailer overturned on the westbound lanes of Interstate 24 just below the Missionary Ridge cut, narrowing traffic down to one lane.
The vehicle was carrying a load that was taller than it was wide and overturned as it headed toward exit 181, according to the Chattanooga Police Department. An officer called for a wrecker at 2:15 p.m.
Chattanooga police said a crash involving three vehicles on the northbound lanes of Interstate 75 resulted in injury and is holding up traffic.
The crash occurred close to the Ringgold Road exit in East Ridge.
In both crashes, officers were unsure how long it would take to clear the roads.
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