A mid-air collision involving two small planes in the south-western US killed at least two people, authorities said.

Federal air safety investigators said two people were on board each plane as they collided on Wednesday (Thursday AEDT) near Marana Regional Airport on the outskirts of Tucson in Arizona.

One plane landed uneventfully with the other hit the ground near a runway and caught fire, the US National Transportation Safety Board said, based on preliminary information before its investigators had arrived.

The Marana Police Department confirmed two deaths after responding to the crash, but gave no additional details.

Last week in Arizona, one of two pilots died on a private jet owned by Mötley Crüe singer Vince Neil after the aircraft veered off a runway in Scottsdale and hit a business jet.

Four major aviation disasters have occurred in North America in the last month. The most recent involved a Delta jet that flipped on its roof while landing in Toronto and the deadly crash of a commuter plane in Alaska.

Late last month, 67 people aboard an American Airlines passenger were killed when an Army helicopter collided with it in Washington, DC, marking the deadliest aviation disaster in the US since 2001.

Just a day later, a medical transport jet with a child patient, her mother and four others aboard crashed into a Philadelphia neighbourhood on January 31, exploding in a fireball that engulfed several homes. That crash killed seven people, including all those aboard, and injured 19 others.

The airport in Marana has two intersecting runways but operates without an air traffic control tower.

A multimillion-dollar project was underway to build a tower but delays due to the COVID-19 pandemic pushed back construction. Tens of thousands of flights arrive and depart from the airport annually.