SEATAC, Wash. -- An Alaska Airlines 737-400 was evacuated Thursday at Seattle-Tacoma International Airport after hazy smoke appeared in the cockpit shortly after landing, officials said.

No major injuries were reported and the source of the smoke remained under investigation, said Mike Fergus, a Federal Aviation Administration spokesman, and Paul McElroy, an airline spokesman.

The crew of Flight 529 from Los Angeles reported a potential landing gear problem 23 minutes before landing, but all appeared normal until "a light gray haze ... not thick smoke" appeared on the flight deck five minutes after touchdown and shortly after the plane cleared the runway, Fergus said.

The plane was approaching Concourse C after touching down at 9:11 a.m. when the captain reported the smoke, a Sea-Tac spokesman told KIRO 7 Eyewitness News.

Soon after, at 9:17 a.m., the pilot ordered that evacuation chutes be deployed on the taxiway, Fergus said.

Two passengers reported minor injuries, such as twisted ankles, and the co-pilot was given "very precautionary medical attention" for smoke inhalation, McElroy said.

"It was a fast evacuation, as emergency evacuations always are, but it was very orderly," he said.

The plane carried 103 passengers and a crew of five.

The episode began when electronic indicators on the flight deck failed to verify that the nose landing gear had lowered and locked into place properly while the plane was over the Seattle area and 5 to 10 miles from the airport, McElroy said.

Fergus said the pilot reported the potential problem at 8:49 a.m., but everything appeared OK on a fly-by past the airport control tower and the plane was cleared to land.

The source of the smoke could not be immediately determined, nor could investigators who initially examined the aircraft say whether there was any connection between the smoke and the landing gear. The plane was towed to a repair hangar for further examination.

An airport spokesman told KIRO 7 Eyewitness News that some tripped circuit breakers may have caused the smell of smoke. No fire was found.