Hillsborough, N.C. — One person was killed and several others were injured Thursday in a wreck in Orange County that caused traffic delays and lane closures on Interstate 85 for most of the day.

Slideshow     I-85 tractor-trailer wreck

The North Carolina State Highway Patrol said a tractor-trailer carrying cement mixers traveling southbound on I-85, overturned around 9:45 a.m. near the N.C. Highway 86 exit (mile marker 165), knocking off the mixers.

That triggered another wreck involving a tanker, a Mazda Protégé, a Ford Crown Victoria and another tractor-trailer hauling cardboard that caught on fire.

The driver of the tractor-trailer that caught fire died, State Trooper Greg Ingram said, but his identity hasn't been released.

Six people, including the driver of the cement truck and a 7-year-old girl, were taken to UNC Hospitals in Chapel Hill, where, spokesman Tom Hughes said, four people from the wreck were treated for injuries, as well as two passersbys who stopped to help.

Four of the of the patients from the wreck were listed in fair condition, Thursday afternoon, Hughes said. One of the passerbys was later released; the other was listed in good condition.

A seventh person was taken to Duke University Hospital for treatement.

Both directions of I-85 were closed for about five hours, causing traffic backups for miles, as emergency and clean-up crews worked at the scene. A small section of the right southbound lane was blocked for an additional six hours, reopening just after 8:30 p.m.