Ottawa police say several people have come forward in the case of a music teacher, who is also the drummer in Prime Minister Stephen Harper’s band, since the man was charged with sexual assault.

But police don't yet know whether there are more victims.

Police charged 43-year-old Phillip I. Nolan on Thursday with five counts each of sexual assault, sexual interference and sexual exploitation in connection with alleged incidents while Nolan was teaching at a school in the Ottawa-Carleton District School Board (OCDSB).

The alleged assaults involve two girls and occurred between 1998 and 2000 while Nolan was teaching Grades 7 and 8.

Police said the investigation into Nolan began in November 2013 after a complaint about a sexual assault on a minor.

Investigators said there could be more victims and on Friday, Staff Sgt. Angela McDade of the Ottawa police sexual assault and child abuse unit said they have received several calls related to Nolan’s case, but she could not say whether the callers are victims or witnesses or people providing tips.

Police are looking into the calls to determine their connection to the case.

'He maintains his innocence,' defence lawyer says

Nolan's Toronto-based lawyer, Lou Strezos, said Nolan "maintains his innocence."

"My client is going to be vigorously defending these charges in open court," Strezos said on Friday. "... We have no disclosure whatsoever at this point. We look forward to getting the material and moving the case through the court system as soon as we can. 

"He maintains his innocence, he's presumed innocent, and we will deal with it appropriately in court."

Nolan was released from custody Thursday on a $5,000 bond. Under the terms of his release, he is not allowed to come in contact with anyone under 16 years old without the consent of their parent or guardian. He also can't communicate with the alleged victims.

None of the allegations against the teacher have been proven in court.

PM knew Nolan for 'number of years'

Phillip Nolan Harper Drummer Charged

Phillip Nolan, far right, the drummer in the band that often accompanies Prime Minister Stephen Harper, is facing multiple charges of sexual assault and sexual interference. In the photo, Harper and his band Herringbone receive applause after performing in Toronto on Dec. 1. (Chris Young/Canadian Press)

The Prime Minister's Office confirmed Thursday that Nolan is the drummer in the band Herringbone, and that Harper has known Nolan for a "number of years."

Neither Harper nor his office had heard of any concerns regarding Nolan in the past, the PMO added.

Nolan has been working as the music teacher at Avalon Public School in the east Ottawa suburb of Orleans but he was removed from the classroom and assigned administrative duties after police began their investigation, according to the Ottawa-Carleton District School Board (OCDSB).

He is now suspended, the release added.

Nolan's online profile with the Ontario College of Teachers indicates he earned his teaching certificate from Queen's University in Kingston in 1994.

In 2005, Nolan also received the Arts Educator of the Year award from the Ottawa-Carleton District School Board Arts Advisory.

Anyone with information about this case is asked to call Ottawa police at 613-236-1222, ext. 5944 or Crime Stoppers at 613-288-8477.