SAN JOSE — A suspicious vehicle was spotted in a neighborhood plagued by a rash of home break-ins. Residents reacted immediately.

Frantic messages went out through group texts. A half-dozen people converged on Crystal Springs Drive in the city’s Almaden area to make sure the unoccupied car — a dented, black BMW with tinted windows and mismatched license plates — didn’t disappear before police arrived.

“This is what it’s like for us now,” said Mary Ellen Distinti, among the people watching from a distance as a third San Jose police cruiser arrived on the scene. “We’re all listening to the scanner. We take turns driving around. I know it might sound insane. But what’s the alternative?”

As burglaries have tripled in the Almaden Valley and community alarm has grown,

Mayor Sam Liccardo and other officials are scheduled to appear at a meeting Wednesday night at Bret Harte Middle School.

But Almaden Valley is emblematic of a broader trend in the Bay Area’s largest city.

Frustrated by a shrinking San Jose Police Department and growing response times, fed-up residents are banding together to find their own solutions — in some cases taking “neighborhood watch” to a whole new level. They’re communicating on social media about local crime activity and some Almaden Valley and other neighborhoods are even resorting to hiring private security to patrol their streets.

“It’s stating the obvious to say that our system is broken,” said David Noel, president of the Erikson Neighborhood Association, a separate community located near Oakridge Mall that also uses private security. “Security can respond if you call them about anything that seems suspicious. The police just don’t have time to do that anymore. So there is a peace of mind there.”

The police department has about 900 sworn officers who can hit the streets, more than 100 fewer than is budgeted and nearly 30 percent less than in 2008. Today, there is one dedicated burglary detective for a city of nearly 1 million residents as the SJPD has trimmed back investigative teams to maintain patrol staffing.

Overall property crimes actually were down 3.7 percent in 2014 throughout the city. That’s not the case in Almaden Valley, where the median sales price of homes in that zip code is about $1.2 million, according to real estate information service DataQuick CoreLogic.

Over a three-month period between October to January, there were 180 burglaries compared to 55 in the same time frame a year earlier, according to the SJPD.

“It’s completely out of control,” said Distinti, who has lived in Almaden Valley for 16 years and works from home . “It’s like the Wild West here.”

Believing that the law-enforcement calvary wouldn’t be riding over the hill anytime soon to help, Distinti and others decided to circle the wagons. Using the Nextdoor social networking service, Distinti organized a meeting a few days before Christmas that she said drew about 80 residents.

They listened to a presentation from TAPS, a San Jose-based private-security firm headed by a current SJPD officer, which began providing private patrols about two years ago. About 100 households decided to pay $40 a month for the service.

The department is currently is reviewing whether it’s a conflict for an officer to also operate a private security company. But Distinti believes there would be even more burglaries without the presence of TAPS.

Private security has been tried in the Almaden Valley before — although it faded away because not enough residents were interested.

In 2013, the Hamann Park Neighborhood Association, located near the Campbell border, banded together amid a wave of property crime and vandalism at the community park.

For about eight months, security guards hired by the association patrolled the park on foot daily. By the end of that stretch, the community felt like it had taken back its park.

“We’re still united and proactive and aware of what’s happening,” said co-president Vince Navarra, describing how groups of neighbors walk the area at night with flashlights to deter potential criminals.

Over in the Erikson neighborhood near Oakridge Mall, about 70 households have joined to use TAPS, which was hired in June 2013 after break-ins increased — primarily targeting vehicles.

“It’s impossible to say if they’re preventing crimes,” Noel said. “That’s because it’s impossible to prove a negative and crime tends to move around anyway. But you just hope that they’re seen and being proactive about potential problems.”

Just how many neighborhoods, homeowners associations and apartment complexes are hiring private security is unclear because neither SJPD nor the city requires security companies to register with them.

“We look at it this way: More is always better,” said Officer Albert Morales, a department spokesman. “A private security company is an extra pair of eyes. They are another resource. It can be a good thing.”

Another type of proactive effort is occurring on the city’s East Side as residents conduct weekly “Night Walks” to help ward off violent crime.

That spirit of cooperation is what Steve Kostie, a 10-year Almaden Valley resident, considers most important. In his neighborhood, many are working together to try to be part of a solution.

“The good news is there’s definitely more awareness and people know each other better,” Kostie said.

During an interview Friday morning, he was listening to a scanner app on his cell phone. About a half-hour earlier, he had been one of the residents concerned about the black BMW.

The Almaden Valley break-ins generally have occurred during the day when families are away at work and school. The BMW matched the description of a car previously seen driving around the neighborhood.

Madeline Chiavetta is on a group text with 10 people in Almaden Valley. A friend alerted everyone that the car was parked in front of her house, and Chiavetta drove over to the street. And waited with a group of other residents as police officers investigated.

“We’re definitely on edge,” she said, waiting with others to find out what the police learned.

Then word began to circulate that police determined the car owner was a painter working at another house on the street.

“It’s not a false alarm to me,” Chiavetta added. “That car had different plates on the back and front. It’s still suspicious.”

And residents in Almaden Valley are convinced that such vigilance is making a difference.

A community safety meeting will be held Wednesday at 6:30 p.m. at Bret Harte Middle School. San Jose Mayor Sam Liccardo and Councilmember Johnny Khamis are scheduled to be among the officials present.