PORTLAND — Former Maine State Police Chief Andrew E. Demers has been indicted on charges of gross sexual assault and unlawful sexual contact in a case involving a young member of his family.

Demers, 73, of New Gloucester, who served as chief of the state police from 1987 to 1993, faces 30 years in prison if convicted of gross sexual assault, a Class A felony.

Demers was arrested March 17 and initially charged with Class B unlawful sexual contact with a person younger than 12. He was released on $5,000 cash bail.

But according to the indictment, released by a Cumberland County grand jury this week and announced Friday, that charge has been upgraded to the Class A and B felonies, which prosecutors say occurred in February and March of this year.

Cumberland County Sheriff Kevin Joyce said in March that a tip from a previous employee of Demers’ at the Maine State Police spurred the investigation. Detectives then investigated reports of “an ongoing unlawful sexual contact situation,” and interviewed witnesses and a suspected victim.

Joyce said Demers admitted to detectives that he had unlawful sexual contact with a younger member of his family. The sheriff also confirmed that Demers attempted suicide before the investigation began.

Demers served 26 years with the Maine State Police and held the position of chief from 1987 to 1993, when he retired.

In 2003, Demers was the most decorated officer in state police history and was named a “Legendary Trooper,” the Sun Journal reported at the time.

Cumberland County District Attorney Stephanie Anderson, who is prosecuting the case, was out of the office Friday and could not be reached for comment.

Demers’ attorney, Walter McKee of Augusta, did not immediately return a phone call Friday afternoon.