At dinnertime Wednesday, a steady stream of students walked into one of three cafeterias at the University of California, Davis.
Lt. Nader Oweis, a campus police spokesman, noticed two women leaving their backpacks in lockers -- unlocked -- at the dining commons entrance.
"If I were a thief, I could walk in and grab what I need and walk out," Oweis said. "Nobody would know."
A surge of thefts on campus recently has prompted UC Davis police officers to step up their enforcement efforts by implementing a decoy program.
Officers pose as students and leave backpacks and laptops in the library and cafeterias as bait.
"There's been a lot of thefts," Oweis said. "The numbers are increasing and we are trying to combat that, but it's still a safe place."
In 2005, there were 219 reported thefts, according to police data. At the beginning of November this year, the number stood at 268.
Authorities say it isn't clear who's stealing the backpacks, textbooks, laptops, iPods and other electronic devices. Lt. Matthew Carmichael, head of the investigations division, said it may have been a group of people or an individual who found out that the library and cafeteria provide easy targets.
Students, concentrating on academics, often leave their belongings unattended at these places, Carmichael said.
"The students are so busy, and we are in a low-crime area," Carmichael said. "They are so focused that when they get up from the table for a break, it's not on their mind that someone will walk over to take their things."
Marianne Hawkins, head of circulation services at the university's Shields Library, said a spike in thefts occurred when students were preparing for final exams.
Students who left their laptops in the library when they went to class were shocked to find them gone when they returned.
"People need to be mindful of their own belongings," Hawkins said. She advised students to carry their laptops, backpacks, wallets and other valuable items with them wherever they go, even if they are just taking a short bathroom break or going to another floor to look for books.
"Shields Library wants the library to be a safe place for students to study and we work to maintain that sense of security," Hawkins said.
The decoy program will continue throughout the academic year. Besides using officers as decoys, Carmichael said, the department also has hired students to help with the program.
When the officers or students leave their belongings unattended, other plainclothes police officers will be nearby, watching the items.
Students arrested face criminal prosecution and campus discipline including expulsion, Carmichael said. Theft of an item worth more than $400, such as a laptop, is a felony and punishable by up to a year in prison.