A Glendale Police officer driving northbound saw the two men run to their car, also parked on Brand, and drive east on Wilson, Balian said.
The officer pursued the men, who then drove their black Pontiac north on Maryland Avenue and turned into the parking lot behind the 200 block of Brand, where Pontiac crashed into a parked vehicle, Balian said.
Four men then fled the scene on foot, two through Far Niente restaurant and two down the alley toward Wilson, Balian said.
The victim's diamonds were recovered and two men were detained for questioning, but they were not identified as being involved in the crime, Glendale Police Sgt. Tom Lorenz said.No arrests had been made as of press time.
"Obviously, it was a jewelry heist," Lorenz said. "It was well-orchestrated, but their pitfall was there was an officer who happened on it."
The incident drew about 95% of the department's resources, putting most other calls on hold for more than an hour, Balian said.
Spectators lined the street as police descended upon Brand Boulevard with motorcycles and patrol cars, and a helicopter circling the downtown area. Some of the onlookers were employees who said they were drawn out of their businesses by the noise, and others were shoppers curious about the commotion.
Passersby assembled by the victim's car, which had its front driver- and passenger-side windows bashed in and one rear tire flattened. Splinters of glass covered the ground next to the car.
Shortly after the incident, half a block down the street in an alley adjacent to the Glendale Exchange, startled patrons witnessed two men run past them in what they said was a suspicious manner.