A rash of robberies has hit the campus community this semester. Police say students need to put away their smart phones and start paying attention.

About 20 "night school stick-ups" -- five of which actually happened on campus ­­­-- have occurred in and around SF State in the last 90 days, according to San Francisco police. Suspects are targeting people between 7 p.m. and 11 p.m. who are distracted by their own technology, and reports show perpetrators are using a gun about half of the time.

More police are patrolling the campus and the surrounding areas, but students preoccupied with cell phones and music players also need to be more aware of their surroundings.

"That seems to be the whole connection subjects are keying in on," said Captain Reggie Parson, commanding officer for the investigations division of the university police.

Parson said victims, after being caught off guard, are being robbed for the very things they were fiddling with just moments before. Often left without a phone, victims call in police too late to immediately catch the robbers, said police agencies.

"Inattention is the biggest problem," Parson said. Students are too "wrapped up in different things and they don't pay attention" to what's going on around them.

Attempts to reach victims were unsuccessful, but many students interviewed during the robberies' prime hours were unconcerned with safety.

Only 15 percent of students interviewed actively took steps to increase their safety on campus.

Sarah Loutrel, 23, said she feels uncomfortable walking alone late at night, and tries to find friends to walk with. Loutrel never heard of the university program that sends officers to escort students who request them.

"It's reassuring to know it's there, but I still probably won't use it," she said.

University police have increased both uniformed and plainclothes patrols in the evening and posted alerts all over campus, but Parson said responsibility also lies with citizens.

"Paying attention is the biggest part of it," he said. "That means looking up from electronic devices and noticing where you are and who's around you."

"Then, of course, don't be flashy," he said, referring to smart phones and mp3 players. "Walk with a purpose, look people in the eye and get to your destinations safely. Don't look like a victim. Don't validate them trying to take that risk to rob you."

The Taraval Police District, in which the school is located, covers a large area of San Francisco: west of Twin Peaks and south of Golden Gate Park. The district itself has had 60 robberies in the last 90 days, and 33 percent of them have been at or near SF State.

Night Lieutenant Michael Caplan of the Taraval Police Department said that schools like SF State and City College of San Francisco are always a target for opportunity seeking criminals.

"These events are happening so fast," Caplan said. "It's two to three kids, targeting someone distracted at a bus stop. A lot of times it's just a grab and run."

"They always target schools," Caplan said of the criminals interested in these quick and easy robberies, adding that large groups of people draw criminals. "The problem with the SF State campus is it's very hard to get into and out of."

Caplan expressed concern about staffing as well. Right now, he said, the Taraval station is fully staffed, but a large group of police officers "are coming up on 30 [years] and they're getting ready to pay out."

According to Caplan, those retirees will not be replaced anytime soon. Three classes of police officers San Francisco was going to train this year have been canceled.

The concern for student and civilian safety is reaching into private security as well. Pierre Washington is director of security for Stonestown Galleria.

"There were nine robberies in a row in the middle of last month," he said. "Most crimes are crimes of opportunity, and we're trying to reduce that opportunity the best we can."

To ensure customer safety, Washington's staff of 23 security will escort shoppers to their car, try to remain extremely visibly to deter would-be robbers and have put up a Stonestown public safety alert, informing people of the current situation.

Max Campos, a 28-year-old marine biology major, talked about what he does to stay safe.

"I always sit in the back and near an exit," he said about riding MUNI, where some robberies have occurred. "I keep myself open and pay attention to everything. If I do have earbuds, I keep it at a volume where I can hear everything else."