Three rebels burst into the parliament compound in the Chechen capital of Grozny at 0845 local time (0445 GMT) as deputies arrived for work and began the attack, which lasted until government forces stormed the building.

One blew himself up and two others went on the rampage inside, spraying bullets around as they screamed “Allahu Akbar”, a source who spoke to a witness at the parliament building said.

The remaining two attackers holed themselves up on the ground floor and then blew themselves up when forces loyal to Chechen leader Ramzan Kadyrov stormed the building.

“A special operation to destroy the insurgents has taken place,” Kadyrov said in a brief statement. He said that all the deputies and other people inside the building had been freed.

Earlier, Russia’s federal Investigative Committee said six had been killed. Interfax news agency also reported that the rebels had taken hostages.

At least 17 people were injured in the attack, one of the most brazen in Grozny for years. Russia’s stock, bond and currency markets did not move on the attack and the benchmark MICEX stock index rose by 0.8 per cent.

Growing insurgency

Russia’s leaders are struggling to contain a growing Islamist insurgency in the North Caucasus, a strip of impoverished, mainly Muslim provinces along predominantly Orthodox Christian Russia’s southern border.

The Kremlin had declared victory in its battle with Chechen separatists following two wars in Chechnya to crush separatists since the 1991 fall of the Soviet Union.

The federal government has poured money into rebuilding Grozny, which was devastated in the wars, and Kadyrov boasts that Chechnya is more peaceful than the neighbouring regions of Dagestan and Ingushetia.

President Dmitry Medvedev said last November that strife in the North Caucasus was Russia's biggest domestic problem.

Human rights activists say the Kremlin has relied for far too long on local leaders and security forces whose heavy-handed tactics have exacerbated the insurgency.