Tourists in Istanbul gesture near a historic mosque. A Kurdish militant group has warned that tourists are no longer safe in the country due to its struggle against the state. (Ozan Kose/AFP/Getty Images)

A Kurdish militant group warned foreign tourists ­Friday that they are no longer safe in Turkey as its fighters ratchet up attacks on security forces across the country, an escalation many here fear could bring more deaths and cripple an already unstable economy.

The warning from the Kurdistan Freedom Falcons, known in Kurdish as the TAK, came as the group asserted responsibility for a car bomb attack on police forces in central Istanbul this week. That attack killed at least 11 people near some of the city’s most famous landmarks and was the third bombing this year to hit neighborhoods popular with tourists.

“We warn all tourists who might plan to visit Turkey. . . . You are not our targets, but Turkey is no [longer] secure for you,” the statement posted on the TAK’s website said.

The TAK is a splinter group of the militant Kurdistan Workers’ Party (PKK), which has fought the Turkish state for decades for autonomy for Turkey’s ethnic Kurds. The conflict, which has killed more than 40,000 people, reignited last year after a brief truce between Turkey and the PKK collapsed.

Since then, Turkish warplanes have struck hundreds of militant targets in northern Iraq, where the PKK is based, as well as in Turkey’s southeast, where many towns are majority Kurd. Turkey is home is to roughly 15 million Kurds, who have long been marginalized by the state.

The TAK opposes negotiations with the Turkish government, analysts say, and has attacked hotels and resort towns in Turkey in the past. Its car bomb attacks on security installations and convoys in the Turkish capital, Ankara, have killed more than 60 people this year.

The Turkish government “is responsible for civilian deaths,” the group said. But “we have just started the war.”

Turkey is also embroiled in the conflicts in Syria and Iraq. The tensions have caused the country’s once-booming tourism industry to suffer, and tourists have opted for holidays elsewhere.

The Islamic State has carried out two suicide bombings against tourists in Istanbul and is suspected to have targeted Kurdish peace activists elsewhere in the country.

Last year, Turkish warplanes shot down a Russian fighter jet that had been flying over Syria and allegedly entered Turkish airspace. Russia has thrown its support behind the regime of Syrian President Bashar al-Assad, which Turkey opposes. The incident prompted a nearly 90 percent drop in Russian tourist arrivals from 2015 to 2016, according to Turkish government figures.