Istanbul (AP) — Turkey's state-run Anadolu Agency says at least 47 suspects have been detained in operations across the country following a deadly suicide bombing in Ankara.

In Istanbul, police backed by helicopters arrested at least 20 people suspected of having links to the banned Kurdistan Workers' Party, or PKK. The agency says that Istanbul's anti-terrorism directorate said there were lawyers among those detained.

Wednesday's raids come after President Recep Tayyip Erdogan said Turkey would "redefine" terrorism and terrorists so that legal action can be expanded against anyone supporting terrorism including legislators, academics and journalists.

No group has claimed responsibility for the attack on Sunday, which killed 37 people.