WAKE FOREST, N.C. — Raleigh police said Monday that a seven-hour shutdown of part of U.S. 1/Capital Boulevard in Wake Forest on Sunday was necessary for officers to conduct an investigation into what it called a complicated case.

An accident report into the multiple-vehicle accident indicates that speed was a factor in the crash that killed one person and injured six others. According to the report, the driver involved in the initial crash was going 70 mph in a 55 mph zone when he hit a car, lost control of his sport utility vehicle, crossed over the median into oncoming traffic and hit a pickup truck.

The driver of the pickup truck, Robert Wilder, 40, of Franklinton, died at the scene. The driver of the sport utility vehicle, Allen Little, 38, of Freeville, N.Y., was listed in critical condition at WakeMed Sunday night.

About a mile-long stretch of Capital Boulevard was closed as police tried to figure out who was at fault, leaving many drivers who were stuck in the shut-down also trying to figure out what took so long.

"Seven hours, I mean, you would think they would've been able to figure something out -- open half the road or something," said motorist Gwen Davis.

Raleigh police spokesman Jim Sughrue said that officers dealt with the accident and the traffic shutdown the best that they could.

"With serious injuries and a fatality involved, it's very important to make sure that the scene is investigated thoroughly, and that's what we did," Sughrue said.

Police said it could take days before they finish interviews and announce the full results of their investigation. Detectives said they still need to talk to some of the victims. The results of a drug/alcohol test on the driver are also pending.