FREMONT -- When Fremont resident Kyle Viau dropped off his 2010 Toyota Highlander at his local car dealership for service on Saturday, the last thing he expected when he returned the next day was to find that the SUV had vanished.

"I showed up around 2 p.m., paid for the services and waited for them to fetch the car," said Viau, 32. "Finally after 20 to 30 minutes they informed me that my car was stolen overnight from their secure parking and storage area."

Viau was one of nine customers to have their vehicles disappear from three Fremont dealerships in just over a week, police said. The thefts, investigators say, all involved cars waiting to be serviced or detailed.

The most recent thefts took place at 5851 Cushing Parkway, where Viau took his Highlander in for service at Fremont Toyota, said police spokeswoman Geneva Bosques.

About 5:10 p.m. on Sunday, officers responded to the dealership after employees there reported that five customers' vehicles were stolen from an outdoor parking lot to the rear of the dealership, Bosques said. They included Viau's Highlander, a 2007 Lexus ES, a 2013 Toyota Rav4, a 2012 Toyota Camry and a 2010 Toyota Prius.

All the vehicles belonged to Fremont residents, Bosques said.

"It's likely all the keys were in the cars and the vehicles were left unlocked," Bosques said. "It also appears one of the gates was not secured at night. It was a true crime of opportunity."

Employees who reviewed video surveillance told police that the video showed a white four-door vehicle entered the parking lot, and four to five suspects exited the vehicle about 5:05 a.m. Police have not yet reviewed the video, Bosques said.

In addition to the stolen vehicles, Bosques said, a pressure washer and another customer's vehicle key were also taken.

Employees also told officers that the keys taken were for another Toyota Prius still on the property. That vehicle, Bosques said, was secured to prevent the suspects from returning to steal it.

Then on Monday, police said the dealership reported one more vehicle -- a 2002 Toyota Camry -- had also been stolen off the lot early Sunday.

One day earlier, on Saturday, police responded to Fletcher Jones Motorcars at 5760 Cushing Parkway for a report of a stolen 2007 Mercedes S550. That car, which police believe someone drove off the lot on Friday, was also at the dealership to be serviced.

And the day before that, on Thursday, officers were dispatched to BMW of Fremont at 5720 Cushing Parkway for a report of another auto theft after an employee reported a customer's four-door BMW 528 was taken sometime over the past seven days.

The BMW was last spotted on the lot on Dec. 11, police said.

On Dec. 17, at that same dealership, another customer reported their gray, four-door, 2006 BMW 750I stolen. The victim told police that they dropped off the vehicle at the BMW dealership to be serviced. Investigators say thieves took the vehicle sometime from Dec. 10 to 13 and that both BMWs were likely taken while in a carwash lane waiting to be detailed.

In addition to filing a police report, Viau said he filed an insurance claim for the stolen car and the dealership gave him a loaner car. Meanwhile, police on Tuesday continued to investigate the auto thefts but none of the vehicles had been recovered.

Anyone with information about the incidents is asked to contact Fremont police at fremontpolice@fremont.gov or call the Investigative Unit at 510-790-6900. Anonymous tips can be left at www.fremontpolice.org/tip.

Contact Natalie Neysa Alund at 510-293-2469. Follow her at Twitter.com/nataliealund.