PHOENIX — Authorities are investigating a Christmas shooting at Sky Harbor Airport in Phoenix that left three people injured by gunfire and another person stabbed. Police said the incident was related to a family dispute.

Phoenix police said the evening shooting happened at around 9:45 p.m. at an airport restaurant that is outside the security checkpoints in Terminal 4.

An adult female and two adult males were shot, leaving the female with injuries police describe as life-threatening. The two men were in stable condition and expected to survive, police said in a statement. The man hospitalized with at least one stab wound was in stable condition.

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Family Dispute Escalates to Violence

The group of people all knew each other and had a physical fight that led to one of them pulling a gun, police said.

“I do believe that this was a family dispute that escalated,” Phoenix police Sgt. Mayra Reeson told reporters.

After the gunfire, a man and a girl were detained in an airport parking garage nearby. Police did not immediately release information on possible charges. They were still investigating why the group was at the airport, and whether they were traveling or were there for some other reason.

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Airport Operations Disrupted

The gunfire led to the temporary closure of a security checkpoint at the terminal, the closure of some restaurants and a pause in service at the terminal’s PHX Sky Train station.

“Of course this was scary, this was Christmas evening, everybody’s trying to get home,” Reeson said.

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Unrelated Incident Follows

In what Reeson described as a “completely unrelated” incident after the shooting and stabbing, a man showed up at the airport with a gun late Wednesday night.

“This man received a text message that he believed there was an active shooter at Sky Harbor, Reeson said.

That man then got into an altercation with a police officer and was arrested inside the airport. Reeson said he would be booked into jail. Information on his charges was not immediately available. Sky Harbor, one of the largest commercial airports in the U.S., is a hub for American Airlines and a main connecting point for passengers on Southwest and Frontier airlines.