A Cessna 172S and Lancair 360 MK II collided at 8:28 a.m. near the Marana Regional Airport, just northwest of Tucson, according to preliminary information from the National Transportation Safety Board.

The fixed-wing single-engine planes “collided while upwind of runway 12,” one of two runways at the airport. The Cessna landed “uneventfully” and the Lancair impacted terrain near the other runway and “a post-impact fire ensured,” the NTSB said.

The Marana Police Department confirmed two deaths from the incident. Two people were on each plane, the Town of Marana said in a news release, without sharing their conditions.

In this image taken from video, law enforcement respond to the scene of the crash Wednesday at Marana Regional Airport in Arizona. (Photo Credit: KNXV/AP via CNN Newsource)

The airport is closed while the investigation is ongoing, it said.

“On behalf of the Town of Marana and the Marana Regional Airport, our hearts go out to all the individuals and families impacted by this event,” airport Superintendent Galen Beem said. “This is an unprecedented event, and we are grateful for the swift response from the Marana Police Department and Northwest Fire District.”

The Federal Aviation Administration called the airport an “uncontrolled field,” which does not have an operating air traffic control tower. Pilots often will use a Common Traffic Advisory Frequency to announce their position to other pilots who are in the airport vicinity. Pilots operating in uncontrolled fields are still required to comply with all federal aviation regulations.

An NTSB investigator is expected to arrive Thursday morning to document the scene and examine the aircraft. The FAA is also responding.

The incident follows a recent string of aviation incidents beginning with the January 29 midair collision at Ronald Reagan Washington National Airport, which killed 67 people when a military helicopter and an American Airlines regional jet collided.

Since then, four other aviation incidents have drawn attention to air safety, including the crash of a medevac plane in Philadelphia; a plane that crashed near Nome, Alaska, killing 10 people; a private plane that ran off the runway in Scottsdale, Arizona, killing the pilot on board; and more recently, a Delta Air Lines regional jet that rolled over on the runway on arrival in Toronto.

Even with the past month of aviation incidents, January’s preliminary data from the NTSB shows there was a record low number of airplane accidents nationwide among private and commercial flights. Before the January 29 collision, the last major fatal airplane accident involving a US carrier was in 2009, involving a flight operated by Colgan Air.

However, smaller planes are statistically more likely to experience incidents. The aircraft are not as heavily regulated as those operating under Part 121 rules, the set of FAA rules followed by major air carriers. Private and general aviation aircraft follow different, less strict FAA rules but are still inspected and maintained.

There’s also just a larger number of the smaller planes. The National Air and Space Museum estimates there are more than 340,000 general aviation aircraft around the world and US pilots operate 204,000 of them.

This is a developing story and will be updated.

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