OAKLAND — Thousands of people from up and down California marched in Oakland on Saturday for the largest protest to date against the state’s use of hydraulic fracturing to harvest oil and natural gas.

Environmentalists said they chose to have the March for Real Climate Leadership in Oakland Democrat Gov. Jerry Brown’s home city to highlight their plea for him to take a stance against fracking.

“Fracking is hurting our communities. It is sucking our drought-ridden state of precious water resources, contaminating our groundwater in a region where 25 percent of the nation’s food is grown, and contributing to the impending climate crisis,” UC Berkeley student Eva Malis told a crowd at Frank H. Ogawa Plaza, in front of Oakland City Hall.

“Oil companies had made California citizens feel powerless and silenced, for our governor seems to only be listening to their money,” Malis said.

Fracking is an oil-extraction technique in which water, sand and chemicals are injected into the ground to break up rock formations to allow oil and natural gas to escape for harvest. Environmentalists want Brown, considered a leading supporter of renewable energy, to ban fracking in California — the No. 3 oil producer in the United States.

The Office of the Governor declined to comment on Saturday’s march, but in a Friday news conference at the Capitol, Brown said California “has the most imaginative, integrated strategy to deal with climate change of any political jurisdiction in the Western Hemisphere” but that efforts to do more are hindered by people’s reliance on automobiles.

“As long as Californians are going to drive 332 billion miles a year and consume 14 billion gallons of gasoline and 4 billion gallons of diesel, we’re going to have to have a plan that’s comprehensive, that is stuck to and implemented consistently over time and that deals with all the issues, not just a subset,” Brown said. “As we speak, protesters and nonprotesters are burning up gasoline that is being shipped from Iraq, Russia, Venezuela and coming in on trains.

“Whatever we don’t do here, we’re going to get from somewhere else until we get that moratorium on driving, which I haven’t heard proposed yet,” Brown said.

Environmentalists say fracking wastes millions of gallons of fresh drinking water and puts public health at risk in communities where fracking occurs by threatening groundwater and eroding air quality.

It also “deepens our state’s reliance on fossil fuels, releasing enormous amounts of carbon into the air and worsening the global problem of climate change,” 350.org Executive Director May Boeve wrote in a letter inviting Brown to Saturday’s march.

The march from Frank H. Ogawa Plaza to Lake Merritt via Grand Avenue was preceded by a peaceful rally attended by people of all ages representing hundreds of different schools and environmental groups. Organizers estimated the crowd at 8,000. The Oakland Police Department estimated about 2,000 participated in the march and described the group as peaceful. No arrests were reported.

Peg Mitchell, a 350.org activist, traveled by bus with another 120 San Diegans.

“We’ve assembled here so we can send the message with the rest of our fellow citizens to Gov. Jerry Brown that climate leaders just can’t go out with a legacy of supporting big oil and fossil fuels and fracking in particular,” Mitchell said. “I’m thrilled that we have so many San Diegans willing to (travel), but half of those were high school seniors from the King-Chavez Community (High) School in downtown San Diego, and they did it because they are passionate about getting control of climate change before it’s too late for their generation.”

Staff writer Jessica Calefati contributed to this report. Contact Malaika Fraley at 925-234-1684. Follow her at Twitter.com/malaikafraley.