Chechen separatists are linking a suicide bombing that killed six people on a bus in Volgograd on Monday with a series of ballistic missile attacks that hit the Chechen capital Grozny 14 years earlier.

Kavkaz Center, a Chechen separatist news agency, suggested a link between the Volgograd bombing, noting that it took place on the 14th anniversary of Russia’s ballistic missile strikes on targets in Grozny on October 21, 1999, during the first stage of the Second Chechen War.

Those missile strikes killed 118 people including in Grozny’s central market.

(Translation — The explosion on the bus in Volgograd occurred on the 14th anniversary of the rocket fire on the market and maternity home in Djokhar [the Chechen separatist name for Grozny]).

Russian media has reported that the female suicide bomber, named as Naida Asiyalova, was a native of Dagestan in the North Caucasus. On Tuesday, RIA Novosti reported that the Russian authorities had found a bus ticket from Makhachkala in the bus wreckage. RIA also noted that Asiyalova had purchased her intercity bus ticket in Moscow and traveled to Volgograd. When she reached the outskirts of Volgograd, Asiyalova switched buses and traveled back into the centre, the report said.

Chechen separatist sources also said that the bombing was on “Muslim soil” — a reference to the fact that Chechen and Caucasian separatists and Tatar nationalists view Volgograd as part of Idel-Ural, a short-lived state created in 1917. Tatar nationalists wish to recreate the state as independent from the Russian Federation.

The sources also said that the Volgograd attack came after warnings from Chechen Islamist militant Emir Shaikh Dokku Abu Usman, also known as Dokka Umarov. Three months ago, Umarov called on insurgents to carry out fresh terror attacks against Russian civilians and urged Mujahideen to target the Sochi winter Olympics.

Umarov made his call for insurgents to attack the Sochi Olympics on July 3, in a video that was posted — and almost immediately removed — from YouTube as well as on the Kavkaz Center website.

The Chechen insurgent leader, who considers Sochi to be part of the Caucasus Emirate, the self-proclaimed independent Islamic State — said that the Olympics would take place “on the bones of many, many Muslims killed…and buried on our lands extending to the Black Sea.”

Umarov urged “all mujahedin fighters in the region and Russia’s other subjects not to allow Satanist games to be held on the bones of our ancestors.”

The Chechen separatist leader has previously claimed responsibility for other attacks including the Moscow Metro bombings that killed more than 40 people in 2010, and a 2011 attack against Moscow’s Domodedovo Airport, in which 37 people lost their lives.

Later on Tuesday, Russian media reported that security authorities had defused a home-made bomb with a capacity of 12 kilograms of TNT outside a shopping market in Khasavyurt, Dagestan.

Putin: “Political Forces” Using Islam To Weaken Russia

Meanwhile, Russian President Vladimir Putin accused “some political forces” of using “radical currents” within Islam to weaken Russia, and “create conflicts on Russian soil that can be managed from abroad.”

The Russian President told Muslim clerics at a meeting to celebrate the 225th anniversary of the Central Spiritual Administration of Russian Muslims in Ufa that the “handwriting of terrorists” was all over the Volgograd bus bombing.

“Yesterday in Volgograd a real crime was committed. We are very familiar with the handwriting of these people, these criminals, terrorists, at whose hands many people in the country have already been killed, including representatives of the Islamic clergy,” Putin added.