OAKLAND (KPIX) — Many parts of the Bay Area are under a red flag warning starting at 9 p.m. Saturday night until 9 p.m. Monday. That warning includes the East Bay hills where firefighters say conditions are primed for another big blaze.

That’s why both Oakland firefighters and police officers are concerned about illegal activity happening along Grizzly Peak Boulevard.

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Oakland Deputy Fire Chief Nick Luby says they’ve found video on social media of people lighting fireworks, starting bonfires and drinking alcohol along the pull-outs on Grizzly Peak Blvd.

“I’ve definitely seen fireworks when I’ve been up here and I know it’s not safe,” says Claire Sellick, who comes here to enjoy the panoramic view of the bay.

Regular visitors say they’ve been seeing more people coming to Grizzly Peak this year.

“It’s definitely crowded here because of everything being shut down. Lots more crowds here too,” said Mary Locher, who often drives to Grizzly Peak from her home in Walnut Creek.

Firefighters say bigger crowds aren’t necessarily the problem. Rather, it’s the activities take place once the crowd gets there..

“They’re consuming alcohol, starting bonfires, shooting fireworks into the vegetation,” said Nick Luby, deputy chief of the Oakland fire department.

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Oakland firefighters have already responded to seven fires so far this season in the Grizzly Peak area. It’s the exact same area where the devastating Oakland Hills fire started almost 30 years ago.

“We know the possibility and we learned the possibility the hard way in 1991,” Luby said. “Things haven’t changed with our topography, the homes are still there, the vegetation is still there.”

This year, the brush is drier than ever. There hasn’t been any significant rain in months. Combine that with record-setting heat and Luby says it’s practically explosive.

“I consider it gasoline,” Luby said. “We are surrounded with gasoline looking for an ignition source.”

He says the nighttime closures are necessary to prevent fires sparked by illegal activity.

“It’s one of the most beautiful viewpoints in the area but, if people are causing fires, then I understand why they’re doing it,” Locher said.

“It kind of ruins it for a lot of other people as well who don’t come up here to light fireworks or drink alcohol and drink and drive,” said Claire Sellick.

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Parking in any of the pullouts along a five-mile stretch of Grizzly Peak Blvd. from Skyline Blvd. to Highway 24 is now prohibited from 9 p.m. to 6 a.m. every day. Oakland police will be on patrol and will issue citations if necessary.