OAKLAND (CBS SF) — The FBI is now involved in the ongoing “creepy clown” phenomenon affecting schools in the Bay Area and across the nation, according to a spokesman for the Oakland Unified School District.

“… We suspect some Oakland students may find it amusing to act like clowns or post threatening messages on social media. It is not,” district spokesman John Sasaki said in a statement to students and parents Friday.

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“The students need to know that the Federal Bureau of Investigation (FBI) is now investigating this phenomenon here and across the country and has the technology to find anyone who has been sending threats to others, even anonymously,” Sasaki said.

Schools in the district were placed on lockout Friday after school officials decided the situation was getting out of hand, a district spokesman said.

The lockout, which means officials at each school put strict controls on traffic and people coming in and out, began at around noon Friday and was lifted at 2 p.m.

Sasaki said the idea behind the lockout was to prevent anyone wanting to engage in “creepy clown” antics from coming on campus so teachers wouldn’t be distracted.

No one reported seeing any clowns near campus Friday and school activities went on without a problem.

“I suppose we would also run and take cover. But obviously, they’re trying to get a rise out of people,” said Oakland parent Aparna Rao.

“There’s been a lot going on campus, just kids talking about it,” said 5th Grader Amba Beattie. “They’re saying, ‘Oh no! Clowns are going to kill people.'”

School officials are quite certain that the “creepy clown” sightings and threats in the Bay Area are hoaxes and copycat behavior.

No students, faculty or staff at the schools have been injured because of the threats or sightings.

Clown sightings have been reported throughout the Bay Area all week, most menacingly in Concord, where a mother reported a “creepy clown” tried to kidnap her 1-year-old child on Wednesday afternoon.

The woman kicked the clown in the shin and the person fled.

The Rohnert Park Department of Public Safety said Friday that officers responded to nine clown sightings in the past few days, though nothing criminal is suspected. Sonoma State University has responded to clown sightings as well as an unrelated person in a gorilla suit, according to Rohnert Park police.

Fremont police reported a clown sighting Friday morning. Richmond police confirmed Friday that a clown was seen around 2 p.m. Wednesday near Planet Fitness at 4925 MacDonald Ave., police spokesman Lt. Felix Tan said.

Other sightings and threats have been reported in Antioch, Burlingame and Fairfield this week.

The “creepy clown” threat has been directed mainly toward schools in the Bay Area and across the country this year. The threats, posted on social media sites like Instagram, began earlier this year on the East Coast of the U.S. and have spread to the West Coast.

Most of the threats have been hoaxes. The clowns that have been seen have scared people but few have been dangerous.

The San Francisco Unified School District issued a statement this week that said that, while there were “no credible ‘creepy clown’ reports” in the district, the San Francisco police department and “the district are actively monitoring social media posts, including rumors that clowns would show up at schools threatening to do harm.”

In Concord, police reported a number of copycat incidents including five separate encounters Thursday.

In one incident, a high school student was suspended for posting a selfie wearing a clown costume in front of Clayton High School with the caption, “We’re here!” No charges were filed for any of the incidents because no laws were broken.

Sacramento police tweeted out a message aimed to discourage any pranksters on Friday, promising “Even creepy clowns get sad, when they go to jail” and that any threat directed at a child would be considered a felony.

We dislike having to send this,the clown trend is out of hand-just stop before someone ends up hurt or in jail #sacpd #nomoreclownnonsense pic.twitter.com/3hhoKwYWM8 — Sacramento Police (@SacPolice) October 7, 2016

The East Side High School District in San Jose has responded to the threats by deciding that they will not allow anyone to wear a clown costume or any costume that hides the identity of the student for Halloween.

Whether students will be allowed to wear costumes at all will be decided by officials at each school.

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