US Capitol police arrested a man who had multiple knives, including a bayonet and a machete, in his truck near the Democratic National Committee headquarters in Washington DC on Monday.

Patrol officers noticed a Dodge Dakota pickup truck that bore a swastika and had other white supremacist symbols painted on it around midnight on Sunday. According to pictures released by the police, the truck did not have a license plate but instead a picture of an American flag. The truck also had antlers attached to its front grill.

The owner of the truck was identified as 44-year old Donald Craighead of Oceanside, California. Bayonets and machetes are illegal in Washington DC, according to police.

“Craighead said he was ‘on patrol’ and began talking about white supremacist ideology and other rhetoric pertaining to white supremacy,” according to a press release by the Capitol police.

“This is good police work, plain and simple,” said the Capitol police chief, Tom Manger. “We applaud the officers’ keen observation and the teamwork that resulted in this arrest.”

Monday’s incident comes less than a month after a North Carolina man who claimed to have a bomb in a pickup truck near the Capitol surrendered to law enforcement after an hours-long standoff. Police who searched the vehicle said they had not found a bomb but had collected possible bomb-making materials.

Craighead’s arrest also comes as law enforcement officials prepare for potential unrest and violence during a rightwing rally on Saturday. The rally, titled Justice for J6, aims to defend the nearly 600 insurrectionists who were charged in connection with the deadly 6 January Capitol attack this year.

Top security officials in Congress are expected to reinstall a 7ft fence around the Capitol and authorize the use of deadly force ahead of the rally. The officials have no plans so far to request the national guard as their threat assessment did not warrant their deployment, according to sources familiar with the matter.

“We intend to have the integrity of the Capitol be intact,” said the House speaker, Nancy Pelosi, last Wednesday. “What happened on January 6 was such an assault on this beautiful Capitol, under the dome that Lincoln built during the civil war.”

In an interview with USA Today, Craighead’s father said he did not believe his son had been in Washington to attend Saturday’s upcoming rally, adding that his son had been struggling with drug abuse and mental illness. “He’s not a Trump supporter; I don’t think he’s ever hurt anyone,” said Donald W Craighead.