A fire broke out in the basement at IRS headquarters, but no injuries were reported. (Susan Walsh/AP)

A smoky fire broke out Monday in a monumental federal building near the Mall that holds special significance this month for Washington and the entire country.

The basement transformer fire was reported about 3:30 p.m. at Internal Revenue Service headquarters, in the 1100 block of Constitution Avenue NW.

The building will be closed Tuesday, the IRS said. The agency said that electricity had not been completely restored and that the “air-handling system” was not working.

No injuries were reported in the fire, but the building was evacuated when it broke out. The smoke was mainly in the basement and on the first floor in the building’s southwest corner, near 12th Street and Constitution.

The building closed about 2:45 p.m. Monday, before the fire started, “due to electrical issues with the air-conditioning system,” an IRS spokesman said. He said that about 2,000 people work there and that “a few hundred” were still in the building when the fire broke out.

The fire will not affect processing of tax returns, which is done elsewhere, officials said.