A string of brazen and violent crimes around the University of Minnesota has escalated campus fears, with students asking for more security and U officials taking the unusual step of asking the city to send additional police into the area.

The crimes are happening about as often as they have for the past few years, but the nature and circumstances of some incidents, including a rape near a park and the armed robbery of a student inside a classroom building, have set the U community on edge.

Students are being warned to never walk alone late at night, the student newspaper is halfway through a four-part series on campus crime, and a state lawmaker is holding a hearing next week on campus safety.

Student Chris Graham said the steady stream of university-issued crime alerts this fall has him rethinking his view of the Dinkytown area near campus.

"I always thought of it as a little bubble where kids can come from the middle of nowhere Wisconsin or Minnesota and it's still kind of a safe environment," he said. Now, after the robberies — 28 on or near campus since early August — and the news that some robbers assaulted their victims or threatened them with a gun, students feel things have gotten worse, he said.

"It's disconcerting," Graham said.

Last week, a student-initiated online petition asking for a larger police presence drew more than 3,000 signatures.

Some students are altering their routines in response to the crimes, hoping to boost their odds of staying safe. Others say they are aware of the recent crimes but haven't changed their habits.

Robbers continue to find new victims, most often targeting people for their iPhones and laptops. Most recently, a 21-year-old was robbed at gunpoint of his wallet, cellphone and backpack as he waited at a bus stop on the edge of campus midmorning.

The U typically sees an uptick in violent crime every fall, but this year has also brought some vicious assaults. Two rapes, including one by a man who posed as a police officer, and numerous robberies in which a gun was shown have been among the high-profile crimes.

Saying his 50-officer force is at its limits, U Police Chief Greg Hestness said he's asked for help from the Minneapolis police and the Hennepin County Sheriff's Office. Twenty-five of the 28 robberies he's seen since Aug. 5 occurred in neighborhoods surrounding campus.

"Nobody likes bad news. I have really been getting a lot of bad news here," Hestness said.

In a public safety update sent to students Tuesday, Pam Wheelock, vice president of university services, said that she's asked Mayor R.T. Rybak and City Council President Barbara Johnson to send additional police to patrol near campus. Wheelock said U police have logged 181 overtime hours since Oct. 17 to cope with the crimes.

Second Precinct Inspector Kathy Waite said Wednesday she's already sent extra patrols and extra officers to the neighborhoods near campus.

Her staff also plans to hold a public safety walk with neighborhood residents starting at 7 p.m. Friday at Van Cleve Park, the site of the Oct. 27 rape of a 19-year-old U student. The student was walking home after a party when a man assaulted her while two others acted as lookouts, according to police.

Waite said officers have been urging students to stay aware of their surroundings and to tuck away their cellphones when walking along the street.

"What we keep telling people is you wouldn't put three to five hundred dollars in your hand and walk down the street, so why are we doing it with cellphones?" she said.

Pedestrians are more vulnerable while texting because it allows robbers to approach without notice, Waite said. And in the event of a robbery, the victim is less likely to be able to give a good description of the assailant, she added.

Hestness said that, so far, four arrests have been made in robbery cases since early September.

Parents 'extremely concerned'

Extra Minneapolis officers would join Hennepin County sheriff's deputies sent two weeks ago by Sheriff Rich Stanek. Stanek said it's unusual for deputies to join campus police on what he called "concentrated patrols." He said those patrols will continue up at least until winter break.

Stanek said he was eating his Thanksgiving meal with family when his niece told him that some of her sorority sisters had recently been robbed and assaulted at gunpoint.

"Parents are extremely concerned," he said.

The calls for more police are a temporary measure, but Hestness said he recently proposed that his department take over more regular patrols of the neighborhoods surrounding campus. Such a move would require a new U police headquarters building and at least 30 more officers, he said, but it would ramp up security in the neighborhoods where many students live.

Efforts ramping up

State Sen. Terri Bonoff, DFL-Minnetonka, will open a legislative hearing on campus safety next week. Students have organized an online petition demanding a bigger police presence on and off campus. In addition to texting crime alerts to students, the U is expanding its Gopher Chauffeur service that offers students a free ride home. It will stay open until 3 a.m., an hour later than the usual closing time.

Two of the most brazen robberies have been armed and taken place during the day.

In one, an armed man approached a student in Anderson Hall and demanded her laptop. He fled after she handed him an empty case and screamed, prompting police to issue a shelter in place advisory while they looked for the man, who was never found.

In the most recent attack, Zechariah Jones, 21, who is not affiliated with the U, was waiting at a bus stop on University Avenue in front of University Village Saturday morning when two men approached him and asked him what time it was. One revealed a handgun, demanded his possessions and punched him in the face. The robbers fled on foot.

Jones came away from the assault with a busted lip and feeling shaken to the point that he couldn't go to work. "I lost my pay," he said.

Police were preparing to release a composite sketch late this week of a suspect who posed as a police officer and may be responsible for two sexual assaults Nov. 23-24, one near the U and the other in Fridley. They're also trying to determine whether that same suspect was involved in a third incident, near TCF Bank Stadium.

In that case, a woman said two men tried to abduct her as she walked alone just after midnight Nov. 27.

Staff writer Paul Walsh contributed to this report.

Matt McKinney • 612-673-7329