A man shot a factory worker outside an Amazon warehouse multiple times before being fatally shot himself.
The suspect, who wasn't an Amazon employee or contractor, walked into the grounds of the Amazon delivery hub in the Phoenix suburb of Chandler and shot the unarmed contract worker multiple times on Wednesday at about 9.30am.
Police confirmed a second contracted Amazon employee then shot the suspect, who died at the scene in the warehouse car park.
It is unclear of the motive of the shooting.
Sergeant Jason McCliman said: "We don't know what led up to this. That's under investigation. We also do not know the mindset of the shooter, but we are not looking for any other suspects."
The Amazon worker was taken to hospital in critical condition, but is expected to survive, according to McCliman.
According to police, the other Amazon employee who fatally shot the suspect wasn't injured, but their actions could have stopped an active shooter, he said.
The names of the suspect and two contracted employees have not been revealed.
An Amazon spokesman, Richard Rocha, said the company is working with law enforcement as it investigates the shooting.
He said: "We are deeply saddened by this senseless act of violence in our parking lot.
"We're working closely with law enforcement as they investigate and are focused on supporting our team during this difficult time."
He said the two contractors involved work to support Amazon's delivery network, while the suspect who was fatally shot was neither employed by Amazon, nor any of its contractors.
Operations at the complex were suspended after the shooting and all of its employees and partners were sent home with pay, Rocha added.
The Amazon spokesman did not immediately release any further details about the circumstances of the shooting.
The Chandler complex operates as a pickup zone for contracted Amazon Flex drivers and others, who pick up packages to typically deliver for the same or next day to customers.
News video footage showed police vehicles in the parking lot of the complex later Wednesday with the scene cordoned off by crime scene tape.
Chandler is a suburban community located about 20 miles southeast of downtown Phoenix.
