A small plane crashed into an Anchorage, Alaska commercial building on 29 December, killing at least one person on board, authorities announced. The plane reportedly first clipped an office building in downtown Anchorage. The city's Assistant Fire Chief Alex Boyd said there were no injuries reported on the ground, but it was unclear if the there was anyone else on board.

According to CBS affiliate KTVA, National Transportation Safety Board spokesman Clint Johnson said the plane was part of the Civil Air Patrol. Johnson said the plan contained one person, the pilot, and that it was still unclear what caused the plane crash. The spokesman originally told reporters that it was unclear if it was a sanctioned flight.

Johnson said that the accident happened amid gusty winds and that the agency was not ruling out anything as a cause, The Associated Press reported.

Anchorage police and fire crews responded to the plane crash when a call came in at 6.19am local time. The small plane struck some buildings and then a transformer, which led to a fire breaking out in the car park. One of the buildings hit, known as the Brady Building, is home to the Attorney General's office and two law firms.

KTVA reported that state employees working in either buildings can check the State of Alaska website for closure updates. The streets between Fourth and Third Avenues down from L Street and I Street, where the buildings were located, were blocked off while emergency crews were on the scene.

Municipal Light & Power took to Twitter to update customers regarding any power outages. "Most customers should begin to have their powered restored. Crews working to bring all online. Pwr may be intermittent as crews work," it tweeted.

The Federal Aviation Administration and the NTSB will investigate the plane crash, FAA spokesman Allen Kenitzer told reporters. The Federal Bureau of Investigation has also joined the investigation, but officials have stressed that there is no reason to believe the crash was terrorism related, KTVA reported.

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