OAKLAND — A flier disseminated downtown is urging people to bring bats to next Thursday’s Occupy Oakland anniversary protest, not to smash bank windows, but to “beat the (expletive)” out of anarchists and vandals.

The flier asks residents to “stand up and defend the great city of Oakland” and specifically calls for violence against “black-clad” Caucasians that “use our city landscape as a canvas for their divisive and violent message.”

No one has taken responsibility for one-page post, which leaves no contact information. It claims to be from a group calling itself DOOM — Defend Our Oakland Movement.

Police on Tuesday said they were investigating the source of the fliers and were taking them into account as they prepare for an Oct. 25 protest commemorating the first eviction of the Occupy encampment from outside City Hall and the violent protests that broke out later in the day.

“We obviously won’t tolerate vandalism and crime under the guise of protected First Amendment activity,” police spokeswoman Johnna Watson said.

A flier was taped to the Oakland Tribune’s downtown office over the weekend. Another was reported affixed to a newspaper rack.

The flier comes amid deepening fractures within the Occupy movement over recent bouts of window smashing and graffiti tagging by politically motivated vandals. Occupy supporters didn’t rule out that the flier might have been drafted by one of their own fed up with the ongoing vandalism.

While few people expect bat-wielding residents to battle protesters, the flier’s call to vigilantism stirred bad memories for a city where in 1965 the Hells Angels beat up anti-war protesters near the Berkeley border.

“A sense of dread is not unwarranted when you see something like this,” said Osha Neumann, an attorney and activist who was attacked during a protest in the late ’60s.

“This may be just garbage, but you never know,” he said. “In the past these threats have been very real.”

City officials and community leaders have spoken out against the flier.

Councilmember Ignacio De La Fuente, who has called for the city to get tougher on Occupy agitators, called the author “obviously an extremist and crazy.”

Nancy Sidebotham, who cofounded a citizen’s group earlier this year to speak out against Occupy Oakland-related vandalism, feared a riot if people brought bats to the protest. “Not that I don’t agree that certain people should be done away with,” she said, “but that’s what we have the courts for.”

Phil Tagami, a developer who famously stood inside his building with a gun staring down Occupy protesters last year, said the city should close downtown after 7 p.m. during next week’s protest.

“It’s a shame that it has to come to that, but I’m not sure that the city has the resources to deal with what’s coming,” he said.

Occupy Oakland no longer has the support to draw thousands of people as it did during a general strike last year. Many of its supporters have dropped out entirely, while others have joined similar efforts to open libraries and preserve urban farmland.

But while the ranks of protesters have dwindled in recent months, protest-related vandalism has endured.

Over the summer, black-clad vandals disrupted Oakland’s monthly Friday night Art Murmur event, vandalizing cars and smashing the window at President Obama’s downtown campaign headquarters.

During the city’s Pride Festival in September vandals tried to crash the event and later vandalized several downtown businesses. And two weekends ago, vandals attached themselves to a nighttime anti-war march downtown and began smashing windows of nearby banks and other businesses.

Police made no arrests in connection with any of the incidents.

Several people with connections to the Occupy movement blamed the vandalism on agitators, who they say are predominantly white and from out of town.

Khalid Shakur didn’t know who drafted the flier, but said it reflected attitudes both within the movement and throughout the city. “People are tired of the Santa Cruz kids and the Oregon kids coming here with their one-dimensional agenda of destruction,” he said.

The divide over vandalism — and its impact on declining public support for the movement — led Occupy Oakland on Tuesday to publicly distance itself from a splinter group it associates with the recent attacks on private property.

“We had thousands of supporters; we had so much love from the community, and now it’s just mostly a small group,” said Occupy’s Shake Anderson. ” Thousands of people who marched with us are turning their backs on us now based on this small group of people.”

Contact Matthew Artz at 510-208-6435.