PORTLAND – A member of a Portland police tactical team accidentally shot himself in the foot during a raid to capture an armed fugitive, police said.

Sgt. John Nueslein, a nine-year veteran of the force, was recovering from the injury that occurred Tuesday night when his weapon, a semiautomatic police version of the M-16, discharged as about 15 team members were approaching a High Street apartment.

The team was called in to arrest Scott Stolkner, 34, a convicted felon and a suspect in an armed robbery. While two officers tended to Nueslein, the rest of the team arrested Stolkner and seized a loaded handgun, heroin, Ecstasy and $3,500 in cash.

Deputy Chief Joseph Loughlin said the department planned to investigate why the weapon discharged. Because it was pointed at the ground during the approach to the apartment, the round pierced Nueslein’s boot and the fleshy part of his foot without endangering anyone else, Loughlin said.

Nueslein was treated at Maine Medical Center and then released.

The incident was described as the first in the special reaction team’s 22-year history in which an officer was injured by gunfire.

After being tested at a range, the weapon was found to be functioning properly but had some maintenance issues, Loughlin said.