BOSTON — The Lulz Security group of hackers said in a Tweet that it had launched an attack on the public website of the U.S. Central Intelligence Agency.

The site, http://www.cia.gov, was unavailable for a few minutes on Wednesday evening, immediately after the group announced the attack via Twitter.

“We are looking into these reports,” a CIA spokeswoman said.

The group Lulz Security announced the attack shortly before 6 p.m. East Coast time.

“Tango down,” the group Tweeted, pointing to http://www.cia.gov.

Lulz broke into a public website of the U.S. Senate over the weekend and released data stolen from the legislative body’s computer servers.