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Authorities on Thursday were searching for a person who set fire to a Planned Parenthood in Thousand Oaks the previous night, according to the Ventura County Sheriff’s Office.

Sheriff’s deputies and firefighters responded after a commercial fire alarm was set off at the Planned Parenthood, located at 1200 Hillcrest Dr., around 11:30 p.m. Wednesday, a sheriff’s news release stated.

Investigators initially suspected the fire was suspicious, and arson investigators were dispatched to the scene, sheriff’s official said in the release.

After a thorough inspection, the cause of the fire was determined to be arson, the release stated.

Investigators believed that an unknown person threw a large piece of masonry through the building’s south side. That same person then introduced a flammable liquid into the broken window before using an open flame to ignite it, authorities said.

The building’s fire sprinkler system was quickly activated and extinguished the flames, which were contained to one office. However, there was a large amount of water damage on the first floor as a result.

The attack occurred six weeks after the office was vandalized, the Los Angeles Times reported. Further information was not made available.

The incident came amid a heated debate nationwide about government funding of Planned Parenthood, and days after the organization’s president was grilled by Republicans at a congressional hearing about business practices.

The intense situation began in July when edited videos were released by a group of anti-abortion activists who allege Planned Parenthood has illegally profited off the sale of fetal tissue.

Following the attack in Thousand Oaks, Congresswoman Julia Brownley, D – Westlake Village, released a statement.

“I was deeply troubled to learn that for the second time in two months, the Planned Parenthood clinic in Thousand Oaks has been the target of criminals and cowards who seek to intimidate healthcare workers and deny women their constitutionally-protected rights,” Brownley said.  “These acts of vandalism and arson are just the latest examples of the extreme right’s attacks on women’s healthcare and cannot be tolerated.”

A motive for Wednesday night’s incident was not yet known, according to investigators. Authorities did not have a description of the arsonist, who was wearing clothing to hide his or her identity.

Anyone with information about the fire was asked to contact sheriff’s Detective Michael Rompal at 805-383-8743 or  Additionally, those who wished to remain anonymous can call Crime Stoppers at 800-222-8477.

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