WASHINGTON 

The U.S. Capitol building, where Congress meets, was placed on lockdown Friday morning after reports of an individual carrying something that looked like a firearm.

The U.S. Capitol Police locked down the building at 9 a.m. (1300GMT) till 9.40 a.m. investigating a "person of interest."

The lockdown came in the wake of the shooting deaths Thursday of five police officers by sniper fire in Dallas, Texas during protests of the killing of two black men this week by police in Minnesota and Louisiana and other similar police shootings.

"Out of abundance of caution, the U.S. Capitol and Capitol Visitor Center are on lockdown while USCP investigates a report of a person of interest. Building occupants are advised to shelter in place and await further USCP instructions," Capitol Police spokeswoman Eva Malecki said in a statement.

The lower house of Congress, the U.S. House of Representatives, was in session but went into recess during the incident.