OAKLAND -- For the second time in less than a year, the California Highway Patrol is stepping up to help Oakland's understaffed police department.

City officials announced Monday that they had reached a tentative agreement for the CHP to not only to continue its twice-weekly patrols in Oakland, but increase the service to four days a week.

The added policing would offset the loss of the weekend patrols performed by the Alameda County Sheriff's Office. Those patrols ended Saturday when the sheriff and city officials couldn't come to terms on an extension.

"What this means for the people of Oakland is that our bolstered patrols will continue," Mayor Jean Quan said in a prepared statement. "This help is especially important while we continue to work hard to rebuild the police force by aggressively funding new academies."

With Oakland's police force at its lowest staffing level in well over a decade, the CHP agreed last November to provide 10 officers to help police some of Oakland's most dangerous city streets free of charge for three months. When that agreement expired, the city agreed to pay the CHP up to $162,000 to preserve the patrols through April.

City officials didn't disclose the cost or length of the CHP extension, which has not been finalized. The extension is scheduled for City Council approval on May 7.

The sticking point with the Sheriff's Office centered around liability for workmen's compensation and associated costs that became an issue after a deputy was shot in the foot during a traffic stop in Oakland last month.

The failed negotiations don't bode well for the city's request for county aid in helping rebuild its police department.

Sheriff Greg Ahern said last week that he also didn't anticipate his office being able to meet the City Council's request to help fund the city's upcoming police academies.

Contact Matthew Artz at 510-208-6435.