Distracted driving is believed to be the cause of a deadly accident on Highway 21 Friday afternoon in Madison County, just west of North Zulch.

That accident brought traffic to a halt for hours on a busy Friday afternoon commute.

Investigators say the driver who died may have been looking down at something when the accident happened.

While we don't know what he was doing, investigators say 59-year-old Jack Ernest LeCroy of Spring was distracted when the crash happened around 12:30 Friday afternoon, resulting in his death.

Mangled metal and glass littered Highway 21 near North Zulch after a Delta Mechanical plumbing truck rear-ended an 18-wheeler.

DPS Troopers say 59-year-old Jack Ernest LeCroy died after being transported to the hospital.

The crash closed the highway for more than 3 and a half hours.

Colton Campbell was heading from College Station back home to Tyler, and got stuck for 45 minutes. TxDOT initially estimated the road would be closed until 6 P.M.

"I guess we are going to try and turn around and see if we can find a detour a little shorter. If they are gonna be here 'till six I don't feel like waiting that long," said Campbell.

DPS Sergeant Charles Booker says the driver of the white semi, 37-year-old Ike Sheppard of Caldwell wasn't injured.

"He was stopped and had his truck in neutral and had his emergency flashers going and he looked up and realized that the truck coming up from behind him was not going to stop. He said that he could see that the driver was looking downward and at the last minute he looks up," said Booker.

Investigators say no brake marks were found from LeCroy's box truck.

"Traffic was at a standstill because everything was being diverted into one lane, so they were having to alternate the traffic from the east and the west to allow everybody to get through this construction zone," explained Booker.

"Prayers go out to that guy's family," said Campbell.

The investigation into the accident continues.

Investigators aren't sure at this point if LeCroy might have been on a cell phone or other device at the time of the crash.

Traffic was reopened on Highway 21 around 4 P.M. Friday.

6:48 P.M. Update*
The Texas Department of Public Safety has released the identity of the man killed in an afternoon crash on Highway 21 in Madison County.

59-year-old Jack Ernest LeCroy of Spring died after the commercial box truck he was driving rear-ended an 18-wheeler that had stopped for construction work.

DPS Troopers say cars were stopped waiting to navigate through one lane of construction traffic when the accident happened.

Investigators believe LeCroy was driving distracted and say no brake marks were found at the scene.

The driver of the other vehicle 37-year-old Ike Sheppard of Caldwell was not injured in the crash.

*Update, 4:24 p.m.*
The Texas Department of Transportation says Highway 21 is back open following the fatal wreck. The Department of Public Safety has cleared the accident. A cause is not yet known, and the name of the person killed has not been released.

*Update* TX DOT Now says Hwy 21 will be shut down in both directions until sometime past 6PM

If you are heading towards North Zulch on Highway 21 from either direction, a fatal wreck has traffic backed up.

A south bound 18-wheeler was struck from behind by a commercial box truck on Highway 21. The driver of the box truck was killed when the cab collapsed in on him.

Madison County Sheriff Travis Neeley tells News 3 the wreck scene should be cleared by 3PM.

Neeley says the driver of the big rig was not injured.

Because traffic is backed up for miles, authorities are advising drivers to stay away from the area until the scene is cleared.