At least 16 people were killed and dozens more were injured in a mass shooting spree in Maine on Wednesday evening.

State police in Lewiston, the state’s second-largest city, confirmed an active shooter had attacked a restaurant and bowling alley.

A manhunt involving hundreds of police is currently under way to find the shooter who remains at large.

Police have released a photograph of a dark-haired, bearded suspect carrying what appears to be a semiautomatic rifle, and appealed for information about an “armed and dangerous” 40-year-old man named Robert Card.

According to a police intelligence bulletin, seen by the Associated Press news agency, Mr Card is a trained firearms instructor at a US Army Reserve facility in Maine who was committed to a mental health facility for two weeks earlier this year.

The document also said Mr Card had reported hearing voices and had threatened to carry out a shooting at the military training base in Saco, Maine.

Joe Biden was pulled from a dinner with Anthony Albanese, the Australian Prime Minister, on Wednesday night to be briefed on the situation, and has spoken with the state’s governor, senators and a congressman.

The shooter is understood to have opened fire at Sparetime Recreation, a bowling alley, and Schemengees Bar & Grille Restaurant.

The two locations are 4.2 miles apart, on opposite sides of Lewiston, a small city in the northeastern US state around 35 miles north of Portland.

A police source told local press there had also been shots fired at a Walmart distribution centre.

Locals have been instructed to stay indoors and warned that an active shooter is still at large.

“There is an active shooter in Lewiston,” Maine state police said on Twitter. “We ask people to shelter in place. Please stay inside your home with the doors locked. Law enforcement is currently investigating at multiple locations.”

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

The image of the suspect was posted by state police on Facebook, with a plea for anyone with information about his identity to contact the authorities.

It appeared to have been taken from CCTV footage inside the bowling alley where one of the attacks took place. 

The man was pictured carrying a large rifle and wearing a brown hooded sweatshirt and said to be driving a white Subaru Outback 4x4.

The Subaru Outback was found near a boat dock in Lisbon at 11.20pm local time, about seven miles away, but Mr Card was not inside the car. 

In a separate post, Lewiston Police issued a request for information about Mr Card.

“Law Enforcement is attempting to locate Robert Card…as a person of interest regarding the mass shooting at Schemengees Bar and Sparetime Recreation this evening,” a post on Facebook said.

“Card should be considered armed and dangerous. Please contact law enforcement if you are aware of his whereabouts.”

Horror unfolds at bowling alley

Justin Juray, who owns the bowling alley where the shooting took place, told the New York Times that between 100 and 150 people, including 20 children, were in the building at the time.

Riley Dumont said her 11-year-old daughter was bowling with other children when she heard several gunshots.

The family huddled together in a corner at the bowling alley.  

“I was laying on top of my daughter. My mother was laying on top of me,” Ms Dumont told ABC News, adding that she saw “three or four” victims. 

Melinda Small, the owner of Legends Sports Bar and Grill, said her staff immediately locked their doors and moved all 25 customers and employees away from the doors after a customer reported hearing about the shooting at the bowling alley less than a quarter-mile away around 7pm local time.

Police escorted everyone out of the building, four at a time.

“I am honestly in a state of shock. I am blessed that my team responded quickly and everyone is safe,” Ms Small told The Associated Press.

“But at the same time, my heart is broken for this area and for what everyone is dealing with. I just feel numb.”

The alert for Lewiston was made shortly after 8pm as the sheriff’s office reported that law enforcement agencies were investigating “two active shooter events”.

Officials issued an update around 10pm on their search.

“Avoid the area until authorities give the all-clear,” the statement said. “Seek alternative routes to circumvent the area and any disruptions. If already operating in the affected region, adhere to all instructions issued by local officials, including the shelter-in-place order.”

“We are encouraging all businesses to lock down and or close while we investigate,” the sheriff’s office reported.

Robert McCarthy, a local councillor, said he grabbed his firearms as the “real scary event” unfolded less than a mile from his home. 

“We locked all the doors. We grabbed the guns,” Mr McCarthy told CNN. 

“We’re just waiting to hear that they catch the individual or individuals that did this.”

The shooting is thought to be the deadliest in the US since at least August 2019, when a gunman opened fire on shoppers at an El Paso Walmart with an AK-47 rifle, killing 22 in a shooting that prosecutors branded an anti-Hispanic hate crime.

A further 23 people were injured in the attack, including one victim who died from their injuries in 2020.

The number of US shootings in which four or more people were shot has surged since the Covid pandemic began in 2020, with 647 occurring in 2022 and 679 projected to occur in 2023, based on trends as of July, according to data from the Gun Violence 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.