MOSCOW (AP) — The Islamic State group on Monday claimed responsibility for a deadly attack on churchgoers in Russia's predominantly Muslim Dagestan region.

At least five people were killed and four wounded when a gunman opened fire with a hunting rifles on people leaving a Sunday service at a Russian Orthodox church in the Dagestan city of Kizlyar.

Authorities say the gunman was a local resident, and his wife has been detained for questioning. But police haven't commented on the possible motive for the attack.

Dagestan is a predominantly Muslim region situated between Chechnya and the Caspian Sea. Following two separatist wars in neighboring Chechnya, an Islamic insurgency spread to Dagestan.

A statement from the Islamic State group, posted Monday on an IS-affiliated militant website, claimed responsibility for the shooting, saying a Muslim fighter attacked "a Christian temple" in Kizlyar. The authenticity of the statement couldn't be confirmed, but the website is regularly used by IS for posting militant statements.

The attack happened less than two weeks after several top officials in Dagestan were arrested on embezzlement charges, part of the Kremlin's efforts to strengthen control over the volatile region. The officials, including the head of Dagestan's government, were arrested at their homes before dawn in a swift, military-style operation in Dagestan and flown to Moscow. Observers saw the latest arrests as part of Kremlin efforts to rein in the local elites and establish a degree of control over the economically struggling region.