SAN FRANCISCO, Dec. 6  A scout leader who once sued the City of Berkeley for challenging a national Boy Scout ban on members who are gay or atheist has been arrested on felony charges that for at least five years he sexually abused young males in the troops he led.

Sgt. Mary Kusmiss of the Berkeley police said the scout leader, Eugene A. Evans, 64, a retired high school teacher and for 35 years leader of the Berkeley Sea Scouts, was arrested at his home in nearby Kensington on Tuesday after investigators identified four youths, ages 13 to 17, who said they had been sexually abused by him.

Sergeant Kusmiss said the police began an investigation after a boy and his mother came to them with accusations on Nov. 14.

Mr. Evans is scheduled to appear in Alameda County Superior Court on Friday to enter a plea on 19 felony counts of sexual assault.