MARBLEHEAD, Mass. — A youth hockey coach from Massachusetts has been charged with sexually assaulting a 9-year-old boy.

Christopher Prew, 31, of Marblehead, was indicted Monday on charges of aggravated rape and indecent assault and battery on a child. He pleaded not guilty after his arrest last week.

He is being held without bail at the request of the Essex district attorney’s office pending a hearing Wednesday to determine whether he is a danger to society.

Prew’s sister called the allegations “completely false.”

His attorney, Sean Donahue, said in a statement that his client is “devastated by these alarming accusations,” and had until recently been “intimately involved” with the boy’s mother.

“While child abuse laws aim to protect children, the justice system is set up to vindicate those who are wrongfully accused,” Donahue said.

Police started investigating after the boy’s mother went to police to report that her son said he had been sexually assaulted.

The child’s mother told police the boy’s father had died several years ago and Prew offered to help the boy. Prew took the boy shopping for hockey equipment and taught him to skate. Prew even lived in a rental property owned by the family, where the boy would visit him.

Some of the alleged assaults occurred at that property, according to court records. The alleged assaults occurred from September to January.

Prew was not affiliated with the local youth hockey organization, but co-owned a business called Hot Shot Academy that gives private and group hockey lessons.