At least three people died and 13 were injured on Tuesday morning when militants attacked the parliament of Russia's republic of Chechnya, medics say.
"A vehicle carrying terrorists drove in with cars carrying lawmakers. One of them blew himself up and the other two headed toward parliament," a police source told RIA Novosti.
The source said that parliament has been evacuated and a special operation, headed by Chechen leader Ramzan Kadyrov, is underway to flush out the militants.
Shooting is reported to be continuing at the scene.
Kadyrov has spoken to Prime Minister Vladimir Putin about the situation.
This is the second serious terrorist incident in Chechnya in recent months. In August, a suicide squad launched a massive attack on Kadyrov's home village of Tsentroi.
Chechnya, which saw two brutal separatist wars in the 1990s and early 2000s, has seen relative calm in recent years under Kadyrov, a former militant turned Kremlin ally whom critics have accused of human rights abuses.