A manhunt is underway for a gunman responsible for a shooting in the US that left at least 22 people dead and 60 more wounded.

American media report the shootings happened at multiple locations – including a bar and a bowling alley – in Lewiston, Maine, on Wednesday night (local time).

The Sun Journal reports a third location near a Walmart distribution centre, not far from the other two sites.

Residents of the state’s second-largest city were been told to stay in inside and lock their doors as the active shooter remained at large.

The Androscoggin County Sheriff released an image of the suspect, who could be seen holding a large gun in the firing position.

“We are encouraging all businesses to lock down and or close while we investigate. The suspect is still at large,” the sheriff’s office posted to Facebook.

The bearded gunman, named as 40-year-old Robert Card, is pictured in a long-sleeved shirt and jeans.

The Central Maine Medical Centre in Lewiston issued a statement saying it was “reacting to a mass casualty, mass shooter event” and coordinating with area hospitals to take patients.

Lewiston is part of Androscoggin County and is about 56 kilometres north of Maine’s largest city, Portland.

The incidents reportedly happened at a bowling alley called Sparetime Recreation and at Schemengees Bar and Grille.

The bowling alley is about 6.5 kilometres north of the bar, and the distribution centre is about 2.5 kilometres south of the bar.

Maine State Police and a county sheriff previously reported there had been an active shooter on Wednesday night but did not provide details.

“There is an active shooter in Lewiston,” police said on the social media platform X.

“We ask people to shelter in place. Please stay inside your home with the doors locked. Law enforcement is currently investigating at multiple locations.”

Tweet from @MEStatePolice

The Androscoggin County Sheriff’s Office posted two photographs of the suspect on Facebook, saying he was at large.

President Joe Biden had been briefed and would continue to receive updates, a US official said in Washington.

Maine Governor Janet Mills said she had been briefed on the situation.

Maine senator Angus King said he was “deeply sad for the city of Lewiston and all those worried about their family, friends and neighbours” and was monitoring the situation.

The massacre is the deadliest mass shooting in the US since at least May 2022, when a gunman opened fire at an elementary school in Uvalde, Texas, killing 19 children and two teachers, according to the Gun Violence Archive.

The number of US shootings in which four or more people were shot has surged since the COVID-19 pandemic began in 2020. There were 647 in 2022, and 679 projected to occur in 2023, based on trends as of July, according to data from the archive.

The deadliest US mass shooting on record is the massacre of 58 people by a gunman firing on a Las Vegas country music festival from a high-rise hotel perch in 2017.

-with AAP