Several people are hurt and a courthouse in Santa Maria, California, is closed following “a bomb explosion” Wednesday morning, officials say.

A suspect has been detained and is being interviewed, and the scene continues to be active after the explosion “from an intentionally set improvised explosive device,” said Santa Barbara County Sheriff spokesperson Raquel Zick in a social media post.

Six patients are being treated at Marian Regional Medical Center, according to hospital spokesperson Sandy Doucette.

Three are in fair condition, while the other three are in good condition, she told CNN. “We are providing them with the highest level of care and support,” Doucette told CNN earlier in the day.

Additional details about the incident were not immediately available and a motive has not been determined.

Roads surrounding the courthouse are closed and the public is being urged to avoid the area, Zick said.

In addition to the Santa Barbara County Superior Courthouse in Santa Maria, Santa Maria City Hall, the public library and other city offices in the area closed for the rest of the day, as police investigate “a bomb explosion,” city spokesperson Mark van de Kamp said.

Located in California’s Central Coast, Santa Maria is about 160 miles north of Los Angeles.