Dolores Bojorquez, of Campbell, drove to the store to do some grocery shopping one morning this past fall. When she returned home an hour later, she found that thieves had climbed in through the kitchen window of her locked house and taken at least $10,000 in jewelry -- including her wedding ring -- as well as two new TVs.

Just like that, the 78-year-old retired cook became a victim of the fastest-growing category of crimes in the Bay Area: property crime. For all the attention paid to violent crimes, burglary, theft and auto theft each year touch tens of thousands of local residents -- and often leave them feeling violated.

"Every time you go to get something, you realize it's not there. Every day I seem to notice one more thing," Bojorquez said. "And they can't be replaced."

Property crime in Santa Clara, San Mateo, Contra Costa, Alameda and San Francisco counties jumped by a combined average of 17.5 percent from 2011 to 2012, totaling 261,207 incidents over the past two years, according to data collected by this the Bay Area News Group. In 2012, that amounted to one property crime in the five-county area every four minutes -- and it is continuing to surge in the first few months of this year.

As residents have fretted and seethed, law enforcement officials and criminal justice experts have debated the cause. Many point to police budget cuts, which have forced strapped departments to focus on battling higher-profile or violent crimes. A number of police chiefs also blame the state's efforts to reduce prison overcrowding by sending felons to local jails, where they serve shorter sentences and get back on the streets faster. However, no comprehensive data is available to prove the chiefs' theory.

The Bay Area News Group analysis shows burglaries in the five South Bay, East Bay and Peninsula counties jumped by a combined average of about 23 percent from 2011 to 2012 (not all agencies provided data). Vehicle thefts saw the largest spike, about 35 percent over the same period.

Some Bay Area cities experienced an even larger hike in burglaries, including an increase of 43 percent in Oakland, 63 percent in Gilroy and 59 percent in Colma.

"Property crimes in general are spiking," San Mateo police Chief Susan Manheimer said. "Crews that are loosely connected to each other and the outlying urban areas are coming in and just having a field day in our local communities."

Although most police departments haven't compiled data for the start of 2013, burglary, theft and vehicle theft seem to be continuing to rise in the agencies that provided numbers to this newspaper. During the first three months of this year, burglaries in San Jose rose by 9.2 percent compared with 2012, while vehicle thefts rose by 49 percent. In San Mateo, burglaries in the same period of 2013 were up by 45 percent.

Campbell police Capt. David Carmichael says the combination of lower police staffing levels and the state's effort to reduce prison populations, known as "realignment," make it "hard to imagine that wouldn't result in crime increases."

But San Jose police Sgt. Jim Unland, president of the San Jose Police Officers' Association, says blaming realignment at this stage is a "political red herring" used by some city leaders to draw attention from budget decisions that have shrunk police staffing.

"I'm sure it isn't helping, and it sounds good to say. But show me the hard data," he said. "This (burglary) problem has been going on for two years. "

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However, at least one city is tracking problems with prisoners who were released faster. Antioch police say they are following more than 100 such cases and attribute two homicides and a pair of officer-involved shootings to that group.

"They say these are nonviolent offenders, but that's only their last offense," Antioch police Lt. Diane Aguinaga said. "These people are violent."

Not every city saw property crime spike last year. Cities such as South San Francisco and East Palo Alto saw burglaries and theft drop by double digits. In South San Francisco, which was one of the epicenters of a burglary rush last spring, police zeroed in on the crime near a cluster of hotels where crooks targeted the electronics and luggage in visitors' rental cars. Officers ran extra patrols and trained clerks to watch for thieves. The result of those efforts, South San Francisco police Sgt. Bruce McPhillips said: Burglaries were down by nearly 15 percent in 2012 from the year before.

Police and experts agree that Great Recession-driven budget cuts that left the region's biggest cities -- San Jose, San Francisco and Oakland -- with up to 25 percent fewer officers are a key factor in the spike.

San Jose had more than 1,400 sworn officers in 2008 but currently has just 911 officers ready to deploy. In September, the department reassigned four of the six burglary detectives to street patrol. That left two San Jose detectives dedicated to investigating the 1,369 reported burglaries for the first three months of the year, according to Officer Albert Morales.

"When you look at the last 20 years, there's been a substantial drop in crime from the early 1990s, and a great deal of that was attributed to policing strategies," said Alex Gerould, assistant professor of criminal justice at San Francisco State. "When you have a 20 percent cut (in police), you reduce the ability of police to mobilize specialized task forces that saturate particularly troublesome neighborhoods and areas."

Less intense enforcements allow the small percentage of thieves responsible for most crimes to find "seams and opportunities," Gerould added.

That's why Unland, of San Jose, is suggesting a regional burglary task force similar to the Regional Auto Theft Task Force in Santa Clara County. In an era of dwindling manpower, he said, each agency in the county could contribute an officer -- part-time or otherwise -- to a task force focused solely on catching burglars wherever they operate.

Criminals tend not to respect jurisdictional lines. In January, a former San Jose State football player was sentenced to seven years in state prison for burglarizing Bay Area homes in multiple counties.

Kariem McFarlin, of Alameda, targeted affluent homes, including the Palo Alto residence of the late Steve Jobs, where he stole $60,000 worth of Tiffany & Co. jewelry, several Apple gadgets, kitchen appliances and the California driver's license of the late Apple CEO. Prosecutors say McFarlin also was responsible for burglaries in Alameda, Marin and San Francisco counties.

"Criminals don't care about city boundaries," Unland said. "These aren't the kids who do this every once in a while. These are the ones that commit burglaries every day."

Contact Mark Gomez at 408-920-5869. Follow him at Twitter.com/MarkMgomez. Contact Joshua Melvin at 650-348-4335. Follow him at Twitter.com/melvinreport. Contact Robert Salonga at 408-920-5002. Follow him at Twitter.com/robersalonga.