In a statement late Wednesday night, the Lewiston Police Department said the 40-year-old person of interest Robert Card, who is currently absconding, should be “considered armed and dangerous”, CNN reported.

"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. CARD should be considered armed and dangerous. Please contact law enforcement if you are aware of his whereabouts," the statement added.

On Wednesday evening, the police department said that had responded to two locations in Lewiston -- a restaurant called Schemengees, and Sparetime Recreation, a bowling alley, the BBC reported.

The two locations are at a distance of 6.5 km from each other.

Also confirming the incident, Maine State Police said in a post on X: "There is an active shooter in Lewiston. We ask people to shelter in place. Please stay inside your home with the doors locked."

The Central Maine Medical Center also said that it was reacting to a "mass casualty, mass shooter event" and is coordinating with other hospitals in the area to treat the injured.

Although the number of injured persons was not immediately clear, but reports have suggested that at least 50 to 60 people were hurt.

Meanwhile, the Androscoggin County Sheriff's Office released two images of a suspect, showing a bearded man in a brown sweater carrying a firearm walking into a building.

"Law enforcement in Androscoggin County are investigating two active shooter events. We are encouraging all businesses to lock down and or close while we investigate. The suspect is still at large," the Office said in a Facebook post.

Police also shared a photo of a white vehicle, saying its front bumper was believed to be painted black, and asked anybody who recognised it to contact police.

Lewiston Public Schools Superintendent Jake Langlais has announced that schools in the district would be closed on Thursday.

A statement from the Department of Homeland Security (DHS) said Secretary Alejandro Mayorkas had been briefed and was continuing to monitor the situation.

"DHS is working closely with our federal, state and local partners to support the Lewiston community," it said.

The Justice Department said that federal agencies were assisting state and local law enforcement.

The White House said President Joe Biden has been informed of the incident, adding that he spoke on the phone with a number of Maine lawmakers in the wake of the mass shootings, reports CNN.

"The President spoke by phone individually to Maine Governor Janet Mills, Senators Angus King and Susan Collins, and Congressman Jared Golden about the shooting in Lewiston, Maine and offered full federal support in the wake of this horrific attack,” it added.

Lewiston is a town of about 38,000 people located about 35 miles north of Portland, Maine.