A mass shooter remains at large in Maine, almost 24 hours after he was suspected of killing 18 people in attacks on a restaurant and bowling alley.

State police and the FBI were searching for Robert Card, 40, a military-trained firearms instructor who was admitted to a mental health facility in July.

CCTV images show Mr Card holding an AR15-style semi-automatic rifle at a bowling alley in Lewiston on Wednesday night, where seven people were killed.

A second attack on a restaurant four miles away killed a further eight people. Three more victims died in hospital. Thirteen others were injured, three of whom remain in a critical condition.

Only one of the victims killed during the shooting spree has been publicly named. He was identified as Bob Violette, a 76-year-old retired mechanic.

Seven other victims had already been identified but their names have not been made public.

His daughter-in-law said Mr Violette was a family man and avid bowling fan who “wouldn’t let you walk out the door without giving him a hug, and a kiss on the cheek”.

She told the Portland Press Herald newspaper he had died attempting to protect children in the bowling alley.

Mr Card’s car, a Subaru Outback SUV, was found at a boat dock in Lisbon, a town about eight miles away from where the shootings took place.

Mike Sauschuck, Maine’s public safety commissioner, told reporters that hundreds of police officers were flooding the state’s streets in search of the gunman.

But he admitted: “We don’t know his location, and I’ll leave it at that.”

Late on Thursday night FBI agents surrounded a property in Bowdoin as they carried out search warrants.