Quebec City police officers have boosted their presence at Laval University, in a bid to collect information about a series of break-ins and sexual assaults at the university last weekend.

As of Wednesday, police had received 15 complaints.

Four women say they were sexually assaulted, and there were 11 complaints of break-ins, Capt. Mario Vezina told CTV Montreal.

Police believe that one person is responsible for the crimes on campus.

The university has increased security around campus, with a guard on place for 24 hours a day at the front door of the residence as well as regular patrols of hallways.

The increase in police presence came as advocates and students organized a vigil on Wednesday night to show their support for sexual violence survivors.

"We are declaring war on rape culture," said Melanie Lemay, an advocate for sexual assault victims and one of the speakers at the vigil.

Rape culture is a term that refers to people blaming victims of sexual assault for being assaulted and justifying male sexual violence.

Three provincial politicians attended the nighttime vigil, offering their support for both the victims and the campus.

"I think it's very important to be there tonight with the young girls of Université Laval," said Minister for the Status of Women Lise Theriault. "It's important to be there and support all the victims."

Her colleague, Minister responsible for Higher Education Helene David, echoed her support for the victims.

"I'm not speaking as a minister, I'm speaking as a woman with a past," she said.

The school's administrators have been criticized for their response to the series of incidents, with the school's rector getting booed and interrupted while speaking at the vigil.

Politicians also criticized Denis Briere, who has been the university's rector since 2007, for not speaking about the incidents until Tuesday.

"I'm a little bit disappointed because the Dean didn't do anything at first and it's important for a Dean," said Parti Quebecois member Mireille Jean. "It's a symbol. It's important for him to say something, to send a strong message that this kind of event, this kind of action is unacceptable."

In the wake of the attacks, the Parti Quebecois is calling for the provincial Liberal party to present a formal strategy on how to prevent and fight sexual violence.

With a report from CTV Montreal's Maya Johnson