LEWISTON, Maine (AP) — A man opened fire at a bowling alley and a bar in Lewiston, Maine in the United States on Wednesday night, killing at least 16 people and engulfing the state’s second-largest city in chaos.

The suspect remained at large as authorities ordered residents and business owners to stay inside and off the streets.

Two law enforcement officials told The Associated Press dozens of people also had been wounded. The officials were not authorised to publicly discuss details of the ongoing investigation and spoke to AP on condition of anonymity.

Lewiston Police said in an earlier Facebook post that they were dealing with an active shooter incident at Schemengees Bar and Grille and Sparetime Recreation, a bowling alley about four miles (6,4 kilometres) away. The Androscoggin County Sheriff’s Office released two photos of the suspect on its Facebook page that showed a gunman walking into an establishment with a weapon raised to his shoulder.

“Please stay off the roads to allow emergency responders access to the hospitals,” police said.

On its website, Central Maine Medical Center said staff were “reacting to a mass casualty, mass shooter event” and were coordinating with area hospitals to take in patients. A woman who answered the phone in the emergency department said no further information could be released and that the hospital itself was on lockdown.

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 7 pm. Soon, the police flooded the roadway and a police officer eventually escorted everyone out of the building four at a time. Everyone in the bar is safe.

“I am honestly in a state of shock. I am blessed that my team responded quickly and everyone is safe,” Small told The Associated Press. “But 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 8 pm as the sheriff’s office reported that law enforcement agencies were investigating “two active shooter events.” Officials issued an update around 10 pm for what they described as a manhunt.

“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.

A spokesperson for Maine Department of Public Safety urged residents to stay in their homes with their doors locked.

“Law enforcement is currently investigating at two locations right now,” Shannon Moss said. “Again please stay off the streets and allow law enforcement to diffuse the situation.”

Governor Janet Mills released a statement echoing those instructions. She said she has been briefed on the situation and will remain in close contact with public safety officials. The White House said President Joe Biden also had been briefed.

Lewiston, about 35 miles (56 kilometres) north of Portland, emerged as a major centre for African immigration into Maine. The Somali population, which numbers in the thousands, has changed the demographics of the once overwhelmingly white mill city into one of the most diverse in northern New England.

Ange Amores, a spokesperson for the city of Lewiston, said city officials are not commenting on the shooting. Amores said Maine State Police were planning to hold a news conference, likely at city hall, to update the public on Wednesday night.

Maine Sen. Angus King, an independent, said he was “deeply sad for the city of Lewiston and all those worried about their family, friends and neighbors” and was monitoring the situation. King’s office said the senator would be headed directly home to Maine once the Senate’s final vote is held Thursday afternoon.