MAKHACHKALA, January 16. /ITAR-TASS/. A counterterrorism operation is underway on the border between the Russian republic of Dagestan and the Stavropol Territory in the North Caucasus Federal District, a spokesman for the National Antiterrorism Committee (NAC) said Thursday.

“The counterterrorism operation regime was imposed at 14:00 Moscow time [10:00 UTC] on a 20-kilometer section of the border,” the spokesman said.

No other details were immediately available.

Russia’s law enforcement agencies and police continue fighting militants in Dagestan over 13 years since the battle phase of the second war against Islamist separatists in the neighboring Chechnya came to an end in 2000.

Attacks on security officials and civilians are frequent in Dagestan, Ingushetia and Kabardino-Balkaria as an Islamist insurgency, once confined mainly to Chechnya, has spread across the volatile region.

The attacks are especially undesirable shortly before the Winter Olympic Games that Russia will host on February 7-23, 2014 in its Black Sea resort of Sochi, located close to the country’s North Caucasus republics.

Russia’s authorities have enhanced security measures ahead of the Sochi Games after recent deadly terrorist attacks on the southern Russian city of Volgograd.

Two suicide bombings left 34 people dead and injured dozens of others in late December in attacks on a railway terminal and a trolleybus in Volgograd, some 1,000 kilometers (620 miles) from Sochi.

A North Caucasus Islamist militant leader, Doku Umarov, wanted both by Russia and the United States, in December called for attacks on the Winter Olympics in Sochi. A large-scale security operation was launched in early January to protect the area that will host the Olympics.