Two people were injured on Wednesday morning, and one man was detained, when the authorities said an explosive device was detonated in a courthouse in Santa Maria, a city around 60 miles north of Santa Barbara, near the California coast.

The man was detained immediately after law enforcement responded to a report of an explosion shortly before 9 a.m. at the Superior Court of Santa Barbara in Santa Maria, Calif., a spokeswoman for the Santa Barbara County Sheriff’s Office said on X. Local news media reported that the man threw a bag into a courtroom, which exploded.

Two people, who had not been identified as of Wednesday afternoon, had sustained “non-life-threatening injuries,” the sheriff’s office spokeswoman said online.

Law enforcement and other emergency responders evacuated parts of the courthouse complex on Wednesday morning, according to local media.

Noozhawk, an outlet covering Santa Barbara news, reported that law enforcement had removed a suspect from the scene shortly after the explosion was reported.

“The suspect was inside the court building and threw a bag in front of Department 9, which is the arraignment courtroom,” Darrel Parker, the superior court executive officer, told the outlet.

“Whatever was in the bag exploded,” Mr. Parker said.

A message on the court’s website said that the Santa Maria campus was closed for the day and that all events on the calendar had been canceled.

The City of Santa Maria said that its City Hall, finance department, city attorney’s Office, public library and recreation and parks department would be closed for the day in response to the incident.

The Los Angeles County Sheriff’s Department said that it was on “heightened alert” and would provide extra patrols at the 37 courthouses where it is in charge of security. “At this time there are no credible threats to any courthouses in Los Angeles County,” the department said in a message on X.