The intense manhunt for the military-trained suspect behind a mass shooting that has killed at least 22 people in the US state of Maine remains ongoing, as officials have revealed disturbing details about the gunman's recent history.
Local police named 40-year-old Robert Card as the suspect in the multiple mass shootings – one at a bowling alley full of families and children, the other at a bar.
Law enforcement officials in Maine described Card as a certified firearms instructor and a member of the US Army Reserves.
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Officials also said Card had recently made threats to carry out a shooting at a National Guard facility in Saco, Maine, and also reported mental health issues, including hearing voices.
A police bulletin said Card had been committed to a mental health facility for two weeks in mid-2023.
It did not provide details about his treatment or condition but said Card had reported "hearing voices and threats to shoot up" the military base.
In addition to the 22 fatalities, between 50 and 60 people were injured in the shootings at Sparetime Recreation bowling alley and Schemengees Bar & Grille Restaurant restaurant in Lewiston, a city of around 37,000 people.
Footage taken outside the Sparetime Recreation bowling alley shows people, including children, running from the scene while separate vision shows the injured being loaded into ambulances.
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There have also been reports of a third shooting location at the Walmart Distribution Centre on Alfred A. Plourde Parkway in Lewiston.
The search for Card has narrowed down on a nearby town after a "vehicle of interest" was located there.
Commissioner of the Department of Safety, Mike Sauschuck, held a news briefing on Wednesday night (Thursday afternoon AEDT) confirming a vehicle of interest was located in Lisbon, 13km south-east of Lewiston.
Residents in both cities are being told to shelter indoors, with police warning the shooter remains "armed and dangerous".
Hundreds of officers are continuing to search for Card.
"Law Enforcement is attempting to locate Robert Card 4/4/1983, as a person of interest regarding the mass shooting at Schemengees Bar and Sparetime Recreation this evening," the Lewiston Police Department said in a statement posted to social media.
"Card should be considered armed and dangerous. Please contact law enforcement if you are aware of his whereabouts."
The Sheriff's Office released CCTV images of the suspected gunman, which appear to show him holding an AR-15-style assault rifle with a telescopic sight mounted on it.
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Central Maine Medical Centre said on its website staff were "reacting to a mass casualty, mass shooter event" and were coordinating with area hospitals to take in patients.
Residents in Lewiston and neighbouring Auburn – with a combined population of over 60,000 people – have been advised to stay inside and lock their doors.
"We are encouraging all businesses to lock down and or close while we investigate," the Lewiston sheriff's office said earlier on Wednesday evening.
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Lewiston Mayor Carl Sheline said he is "heartbroken for our city and our people" over the mass shooting.
"Lewiston is known for our strength and grit and we will need both in the days to come," Sheline said in a statement.
The mayor called on residents to "follow all recommended guidelines and stay home," adding that the city is currently under a shelter-in-place order.
Maine State Police also say they are responding to an active shooter situation in Lewiston in a post on Facebook.
"Please stay inside your home with the doors locked," state police said.
"If you see any suspicious activity or individuals please call 911."
Lewiston is about 57km north of Portland, Maine, and is the state's second-largest city.