Officers responded to several 911 calls reporting an altercation in the 300 block of First Street just after 6 p.m., Los Altos police Detective Sgt. Scott McCrossin said.
Responding officers made contact with two men who told police they were jewelry salesman and had just been robbed.
Four masked men had struggled with the victims and grabbed briefcases containing jewelry from their car, McCrossin said.
One of the salesmen was assaulted during the robbery but was not seriously injured, according to police, and no weapons were seen.
The suspects were seen driving away from the scene with an undisclosed amount of the victims' jewelry.
Similar robberies of jewelry salesmen have occurred recently in Burlingame and South San Francisco. During the incidents, groups of robbers accosted their victims in hotel parking lots or gas stations, stole cases of jewelry, and quickly escaped.
In July 2009, a jewelry salesman from Florida had checked out of his South San Francisco hotel and was loading luggage into his car when at least three suspects wearing dark knit caps and sunglasses approached him and stole a case containing $300,000 worth of jewelry from the car, according to police.
The suspects fled in a white sedan with paper over the license plate.
In November 2009, a New York jewelry dealer was at a South San Francisco gas station when a dark sedan pulled up. Two suspects jumped out and smashed the passenger window of the victim's car before stealing $250,000 worth of jewelry and $10,000 in cash, police reported.
Another pair of jewelry dealers were robbed at a South San Francisco gas station in July when four suspects got out of a Dodge Grand Caravan and took two briefcases containing an undisclosed amount of jewelry and drove off.
In January, a New York dealer was robbed at gunpoint while loading luggage into his car in the parking lot of the Crowne Plaza Hotel in Burlingame.
The suspects fled with jewelry and the victim's watch and cell phone, according to Burlingame police, who reported that six men in two separate vehicles were apprehended later that evening by authorities outside Los Angeles. The stolen property was found in their possession.
The six suspects were charged with robbery and conspiracy and are scheduled to be tried in San Mateo County Superior Court on Jan. 24, 2011.
While acknowledging similarities in the cases, South San Francisco police Sgt. Joni Lee said today there was no evidence establishing a link between the robberies and no update on any suspect information.
"It's a very tight-knit orchestra of people who are doing it," Lee said, "But do we know who they are? No."