The two men charged in connection with a disturbing sexual assault on the UBC campus this weekend made their first court appearance Monday.

UBC resident David Singh Tucker, 28, has been charged with three counts of sexual assault with a weapon, three counts of unlawful confinement, robbery, and disguising his face with the intent to commit a crime.

His alleged accomplice, 23-year-old Yuan Zhi Gao of Vancouver, is charged with breaking-and-entering.

Singh Tucker is no stranger to the courts. In 2009 he was convicted of aggravated assault, unlawful confinement and extortion, and last October he was found guilty of uttering threats.

Police said they know him by more than a dozen different aliases.

Both will be held in custody until their bail hearings: Gao’s hearing is on Tuesday, and his lawyer says he will ask for bail. Singh Tucker will appear via video link on Wednesday.

Around 2:15 a.m. on Saturday, RCMP received a report of a break-and-enter in progress at an apartment building in the 5700-block of Birney Avenue.

Police arrested two men outside the building, began investigating allegations of sexual assault. The suspects and the victims were not known to each other.

Mounties are looking into whether this incident could be related to numerous unsolved sex assaults and prowling cases that have occurred on campus since March.

The University of British Columbia is one of the country’s top universities, but reports of sexual assault have become all too familiar.

Barry Eccleton, UBC director of campus security, says a string of unsolved attacks since 2013 have prompted officials to install security cameras, emergency phones, and improved lighting on campus.

Despite these efforts, the school has still been plagued by reports of a prowler.

“A sexual assault is something that just horrifies us, and something that we don’t like to hear about, obviously,” said Eccleton.

“Certain people will be attracted to an environment like ours, and our job is to make sure that we keep the campus as safe as possible.”

On March 25, a 20-year-old female student was walking alone when the man emerged from a wooded area and grabbed her from behind. He proceeded to shake her violently and force her to the ground, rubbing his midsection against her back in a sexual manner, according to University RCMP.

The woman fought off her attacker - who fled - and called 911. She was treated for minor bruising to the side of her head.

Just one week later, a young woman spotted a man pressing himself against a window in the lounge area of Marine Drive residence Building 5.

The man then made an unsuccessful attempt to break into the building, according to an email that was sent out warning the campus community.

Three weeks ago, Jason Anthony White, a high-risk sex offender wanted on Canada-wide arrest, was taken into custody on UBC campus.

Officials are warning students and residents to take precautions to protect themselves. Suggestions include walking with a friend, being aware of surroundings, and not allowing strangers to "tailgate" into apartment buildings.