A spotter working for the Capitol Police noticed a man walking around with a "long gun" alongside Delaware Avenue NE just outside Union Station, which serves as a central rail station in the heart of the city.
Officers reportedly confronted him and demanded he drop his weapon. When he allegedly refused to comply, police tased him and took him into custody, according to NBC4 Washington.
An officer told the outlet that the suspect was carrying "an AR-15."
The suspect was also carrying a backpack that officers deemed suspicious. The surrounding park was cleared of civilians while police investigate the backpack.
The park where the individual was apprehended is near three Senate office buildings. Police sprinted toward the area when they learned a man with a rifle had been spotted near by.
The US Capitol Police issued a statement on Tuesday afternoon saying there was no reason to believe there was any additional threat to the area.
“USCP Officers just arrested a man with a gun in the park across from Union Station. At this time we have no reason to believe there is an ongoing threat,” the agency said in a tweet. “We are working to gather more information and will put out more details when they are confirmed.”
They later said that they were examining the individual’s belongings “out of an abundance of caution” and advised the public to avoid the park.
Officers said they were unsure of how the individual got to the park with the rifle in hand.