Juan Montano, 32, a native of El Salvador with arrests dating to 1994, many of them weapons related, was arrested just after 2 p.m. outside his house at 2345 Bartlett Ave., in the Fruitvale district, police said.
The arrest team found at least 28 guns, two hand grenades, an ounce of crystal methamphetamine with a street value of about $1,500 and dozens of boxes of ammunition between Montano's two trucks and the house he shares with his mother, police said.
Oakland police Sgt. Jeff Ferguson said in 25 years he had never seen so many weapons seized from one person.
Police members of a special operations group founded last year by a mayoral order also seized what looked like several thousand dollars in cash, two bullet-proof vests, marijuana, a brown bandana and other gang-related items from the suspect.
Many of the weapons were illegal: a sawed-off shotgun and military-style assault rifles. A number of handguns, small pistols and a laser pistol were stored in a Ford Bronco parked in Montano's driveway and in another Ford Escalade, both registered to Montano, police said.
Two other men, who police did not identify, were arrested with him.
Montano is a convicted felon on probation until 2010, during which time he was ordered to stay away from guns as a condition of his probation.
Oakland Mayor Jerry Brown praised police for the arrest Tuesday but called the incident an "outrage."
Despite a long list of previous arrest charges, Montano is considered a probation "no service case load," meaning he was not visited by a probation officer.
While police were making the arrest Tuesday, the mayor was in Sacramento to lobby for increased local authority over parolees. Brown also called for an immediate addition of hundreds of probation officers in the city.
"There are literally thousands of dangerous people in Oakland (who) need to be kept under control," he said. With probation officers monitoring only a fraction of the nearly
17,000 people on probation, he said, the city is "engaged in a very dangerous social experiment."
Six of the 16 homicides this year in Oakland have been Hispanic gang related, officers said. Police will investigate whether any of the weapons seized or the suspects are connected to those crimes. Police said they believe Montano either planned to sell the guns or loan them to other gang members.