Officials in the eastern US state of Maine say the man suspected of killing 18 people in a shooting rampage in the city of Lewiston earlier this week has been found dead, apparently from a self-inflicted gunshot wound.

The officials told a news conference on Friday that the body of Robert Card was discovered near a river in nearby Lisbon, about 10 kilometers southeast of where the attack occurred.

The rampage happened on Wednesday evening at a bowling alley and a bar. It left 18 people aged 14 to 76 dead, and 13 others injured.

Local police had released a photo of the 40-year-old suspect who remained at large in an effort to locate him.

They are investigating details such as the motive behind the shooting.