Turkish leftist group DHKP-C said it was responsible for a suicide bomb attack on the US embassy in Ankara on Friday, according to a statement on a website close to the group.
"Our warrior Alisan Sanli carried out an act of self-sacrifice on Feb 1, 2013, by entering the Ankara embassy of the United States, murderer of the people of the world," the statement said.
More top news
MI5 has reportedly launched two urgent inquiries into how it missed the danger posed by the Manchester bomber, Salman Abedi.
Helicopters are searching for survivors who may be marooned after a weekend of heavy rain.
Thousands of people attended a protest on Copacabana Beach to demand presidential elections as pressure mounts on Brazil's leader to resign.