FAIRFIELD — Athletes from across the Bay Area raised nearly $13,000 Saturday for the families of four Oakland police officers slain last month.

"It's a great tribute," said Oakland police Capt. Ed Tracey, who commands the SWAT and traffic units from which the four officers were lost.

Oakland Sgt. Mark Dunakin and Officer John Hege were fatally shot March 21 by Lovelle Mixon in a seemingly routine traffic stop.

Later that day, Mixon killed SWAT Sgts. Erv Romans and Dan Sakai in a confrontation that also left Mixon dead.

The fundraiser was organized by the CrossFit family of gyms, spearheaded by CrossFit Solano in Fairfield and CrossFit Vallejo.

"We all share that bond. We're all part of that brotherhood," said Vallejo police Officer Dustin Joseph, a trainer at CrossFit Solano.

CrossFit is a physical training program.

that often mimics what public safety and military personnel undergo, such as carrying heavy loads — like a body — for long distances.

However, "anyone can do CrossFit," said Ly Terrado of CrossFit Vallejo.

Trainers at CrossFit Solano contacted their counterparts in Vallejo who agreed to help host and organize the event, Terrado said.

Athletes were asked to donate at least $10 to participate in a workout that included several repetitions of sit-ups, pull-ups, burgees and a 400-meter run with weights that ranged from 10 to 80 pounds.

"This community is close. One of the sergeants, Sakai,. was a CrossFitter and used to work out in Oakland," said Gita Dombrowski, a structural engineer who goes to CrossFit East Bay.

It was Sakai's captain, Tracey, who introduced him to the program, and Tracey was on hand to watch the athletes work out in tribute to his officers.

Vallejo police officers who also are CrossFit members began thinking about the fundraiser shortly after the four Oakland officers' public memorial.

Participants came from as far away as Roseville, and ranged from mothers with toddlers in tow to seasoned athletes who easily ran the 400 meters with 80 pounds on their shoulders.

The Vallejo and Oakland police departments share a close bond, said Vallejo Capt. Lori Lee. Vallejo Chief Robert Nichelini served for 24 years in Oakland, and the two departments regularly train together and support each other, she said. Vallejo cadets are sent to the Oakland Police Academy for further training.

For more information about CrossFit, visit www.crossfitsolano.com or www.crossfit-vallejo.com. For information on how to donate to the families of the slain Oakland officers, visit www.opoa.org.