A California court was sealed off Wednesday after a homemade bomb exploded, with witnesses saying a man had thrown some kind of device in an apparent protest.
Police said one man had been arrested at the scene and two people had been injured.
Lawyer Bill Ausman said he was arriving at the courthouse in Santa Maria, 150 miles (240 kilometers) northwest of Los Angeles, when the commotion began.
“I heard an explosion and someone screaming, ‘It’s a bomb, it’s a bomb, it’s a bomb,'” he told AFP, saying that dozens of people began to flee.
Ausman described how he saw a man tackled by law enforcement as he tried to run.
As he was being taken down he was “screaming that over 900,000 people a year are being killed” by the Food and Drug Administration, the branch of the US government that regulates medication, Ausman said.
“It was really chaotic,” he added.
The courthouse in Santa Maria was the scene of pop star Michael Jackson’s lengthy 2005 trial on child abuse charges.
Police in Santa Barbara County confirmed on Wednesday that one man had been arrested at the scene.
“We have two reports of non-life threatening injuries. One person of interest detained immediately,” a social media post from the local sheriff’s office said.
“Explosion was from an intentionally set improvised explosive device.”
The United States is on heightened alert weeks ahead of a bitterly contested presidential election that has already featured a raft of conspiracy theories about supposed “deep state” plots to harm citizens.
An apparent assassination attempt on Republican Party candidate Donald Trump was foiled earlier this month after the gunman’s rifle was spotted poking out of some bushes at his Florida golf club.