The US National Transportation Safety Board (NTSB) has dispatched an investigation team to Austin, Texas after a small plane crashed into an office building.

The crash, which occurred just before 10:00 am CST, caused a large fire in an office building just north of downtown Austin.

According to the US Federal Aviation Administration (FAA), a Piper Cherokee PA28 was involved in the accident. The aircraft departed from Georgetown Municipal airport north of Austin, which is 33km (20.5 miles) northeast of the crash site, around 9:40 CST.

Officials say injuries were sustained by those in the building and one person remains unaccounted for, not including the pilot who was killed in the crash.

As a result of the accident, the FAA has established a temporary flight restriction (TFR) around the area of the crash encompassing a 7.4km (4nm) radius around the accident site extending to 3,000ft (914m) above ground level.

According to the Aircraft Owners and Pilots Association, the TFR is expected to be lifted quickly as the area is located within Class C controlled airspace near Austin-Bergstrom International airport.

Law enforcement officials have said the incident was isolated and have ruled out any possibility the crash was an act of terrorism, though it is believed that the crash was intentional.

Source: Air Transport Intelligence news