Two people were killed and five injured in a fiery, chain-reaction wreck that involved eight vehicles in Cobb County, police said Friday.

The Thursday afternoon wreck temporarily blocked all northbound lanes of I-75, north of Wade Green Road, and created a traffic mess into the evening, according to police. Investigators believe the wreck happened around 2:20 p.m. as vehicles attempted to slow down for a construction zone, according to Officer Mike Bowman with Cobb County police.

Police believe the driver of a tractor-trailer, Vahid Husic. 40, of Lawrenceville, struck the back of a 2006 BMW X5, causing the BMW to strike two other vehicles, Bowman said. The momentum from the crash caused those vehicles to strike additional vehicles, according to police.

Husic was not seriously injured in the wreck. But the BMW’s driver, identified as Gregory Alan Millsaps, 47, of Marietta, died at the scene of the wreck when his SUV was engulfed in flames, Bowman said.

Five others involved in the wreck were transported to WellStar Kennestone Hospital in Marietta, where one woman died. Barbara Phenicie, 71, of Peachtree City, was the front seat passenger in a 2011 Chrysler Town and Country minivan driven by her adult son. Phenicie was flown to Kennestone, where she was pronounced dead, according to police. Her son and husband, who was riding in the back seat, were also taken to Kennestone with non-life threatening injuries.

The drivers of two other vehicles were also transported to Kennestone, where they were treated for non-life threatening injuries, according to police.

The massive wreck sent flames and billowing smoke into the air near Kennesaw and stretched across all four northbound lanes of I-75 and emergency lanes on both sides of the interstate, according police.

One lane of I-75 was re-opened shortly before 4 p.m. Thursday, but traffic was affected for several miles. All lanes were re-opened by 6:30 p.m.

It was not known Friday afternoon if any charges would be filed in the wreck, which remains under investigation.