Russian officials say three suicide bombers killed at least nine people Tuesday, including seven policemen, in the Chechen capital, Grozny.

The first bomber blew himself up when police tried to detain him near the parliament building in central Grozny. Two other suicide bombers set off their explosives near the same place about 20 minutes later, after more police and rescue workers had arrived on the scene.

There was no immediate claim of responsibility for the blasts, which wounded more than 20 people.

The suicide attacks occurred during the Muslim celebration Eid al-Fitr, which signals the end of the holy month of Ramadan.

The Kremlin is struggling to contain an Islamist insurgency in the North Caucasus.