The extent of the occupants’ injuries was not immediately known, a source briefed on the incident told CNN.

The aircraft involved was identified as a Bombardier Challenger 650 business jet. In a statement, the airport said emergency crews responded to the incident at around 7:45 p.m. ET.

“The City of Bangor and Bangor International Airport can confirm that first responders are still on the scene and are expected to be actively working the site for several more hours before any additional information is available,” the statement said.

Bangor International Airport remained closed overnight on Sunday, officials added.

According to media reports, the Federal Aviation Administration (FAA) and the National Transportation Safety Board (NTSB) have launched an investigation into the crash.

The incident occurred amid a major snowstorm moving toward the northeastern United States.

Federal records cited by CNN show the aircraft was registered to a limited liability corporation based in Houston.

Earlier, the airport issued a brief advisory on Facebook, urging the public to stay away. “Please avoid the airport. The runway is closed at this time,” the post said.