Russia ignoring Chechen rights rulings - group

* Russia ignores Strasbourg court rulings on Chechnya - HRW

* HRW says their implementation key to improving situation

MOSCOW, Sept 28 (Reuters) - Russia has ignored a series of judgments by the European Court of Human Rights on Chechnya, fueling a cycle of violence in the North Caucasus, a prominent rights watchdog said on Monday.

The New York-based Human Rights Watch said not a single perpetrator had been brought to justice despite court judgments naming individuals directly involved in disappearances, extrajudicial executions and torture.

The cases relate to violations during Russian military and intelligence operations in Chechnya from 1999 to 2004.

Rights groups accuse pro-Kremlin Chechen leader Ramzan Kadyrov of ruling effectively since 2004 with a climate of fear to keep control over the mainly Muslim region on Russia's southern flank, where Moscow has fought two wars against separatists in the past 15 years.

An increase in suicide bombs and attacks on security forces in Chechnya and neighboring Ingushetia this year is challenging Moscow's grip on the region. A number of human rights and charity activists have also been shot dead.

Beyond paying compensation and legal fees under the Court's rulings, Russia had failed to fully implement the judgments, ensure effective investigations and hold perpetrators accountable, the group said in a report.

"Full implementation is crucial to prevent abuses from recurring in Chechnya and in other parts of Russia's troubled North Caucasus."

"It carries perhaps the single most significant potential to produce lasting improvements in the human rights situation in this region."

Russian officials were not available for comment.

The report identified Russia's failure to provide access to criminal case files, delays in investigation and legal obstacles preventing investigators from accessing evidence held by Russian military or security services.

It cited examples of the detention of Chechen men by Russian security forces and their subsequent disappearance with little or no investigation into their fate.

"In numerous judgments on cases from Chechnya, the European Court found that the Russian authorities failed to effectively investigate even very strong leads or evidence indicating official involvement in human rights violations," the report said.