LAKEWOOD, Colo. -- Both directions of Sixth Avenue were closed Monday morning first for a suicide, and then later for an unrelated fatal crash.

All lanes of Sixth Avenue were opened by 12:30 p.m.

The police investigation began shortly after 3 a.m., as a Denver police officer attempted to stop a vehicle on westbound Sixth Avenue. The suspect vehicle fled the scene and the officer lost sight of it. A few minutes later, he found the vehicle unoccupied.

The officer began searching for the driver on foot. A short time later, the officer found the suspected driver on the eastbound lanes of Sixth Avenue with a gun.

"At no time was there a police pursuit or anything of that nature," said Denver police Detective John White. "Officers simply found the car a short time after and attempted contact. The officer found the suspect a short distance away and he shot and killed himself."

Denver police are investigating the shooting as a suicide.

The road opened three hours later, but at 8:23 a.m., one person was killed in a car crash on eastbound Sixth Avenue near Bryant Street, just after Federal Boulevard.

Three people were outside their cars, assessing the damage from a non-injury crash involving their three vehicles when a fourth vehicle going eastbound hit one of the cars involved in the original accident. That car then slammed into one of the drivers, who was standing on the highway, White said.

That victim died at the scene. Two other people were transported to the hospital with minor injuries.

The names of the victims from both incidents are being held pending positive identification and notification of next of kin.