Contra Costa County residents are on alert Thursday after two more car fires — just the latest in a string of suspicious and "likely related" blazes — broke out a few minutes apart in Brentwood.
The first fire was reported at 3:28 a.m. on the 1100 block of Hollowbrook Court in Brentwood. Along with charring the Chevrolet Avalanche, it damaged the residence's garage.
The homeowner, who only identified himself as John, said a neighbor happened to be awake early Thursday and was heading to work when he noticed their car was ablaze. So he rang the doorbell and woke up the family, giving a couple, their twin 6-year-old girls and their grandmother time to make it out safely.
John was thankful his neighbor rang the alarm.
"We could be in the hospital or worse," he said. "It's as simple as that. That's why I'm frustrated. I don't understand how anyone would choose to do that."
The second fire broke out just a mile away at 3:36 a.m. It scorched a car parked in the driveway of a home on the 1800 block of Highland Way.
Both fires are being investigated, but it's too early to say if these are acts of arson. They are suspicious, though, because of the time they broke out and their proximity to each other.
Investigators were not ruling out that the string of fires are connected to one individual or group.
“We do know that some characteristics of the fires have some commonality," they said. "We believe that to be the work of the same person or group of people.”
A neighbor's surveillance system captured a person walking by his house before one of the two Brentwood fires ignited. Fire investigators said the person captured on camera is a person of interest, not a suspect.
Thursday's scare follow a pair of fires — one in Walnut Creek and the other in Lafayette — that destroyed two cars early Wednesday morning. Another car burned in Martinez early Monday morning. The recent slew of blazes are "likely related," according to Contra Costa County Fire investigators.
Car fires are suspicious by their very nature, according to the Contra Costa county Fire Protection District, but there are indications of arson in the Lafayette and Walnut Creek blazes.
People who live in these areas say the blazes are suspicious enough to make them take precautions.
"This is a very quiet neighborhood and to wake up in the middle of the night and see a car on fire and then find out that it could be arson is quite scary," John Cumbers said.
John, the homeowner who lost his Chevrolet Avalanche, added that the fires are unnerving.
"There's no reason to do that," he said. "You're putting people's lives at risk. I don't understand the reason for it."
Anyone with information or surveillance footage pertaining to the fires is asked to contact the Arson tip line at 1-866-50-ARSON.
A third car fire on Thursday also broke out in Orinda, but that one was deemed accidental.
NBC Bay Area's Cheryl Hurd contributed to this report.