The European Court of Human Rights (ECHR) ruled on Tuesday that Russian authorities had failed to effectively investigate the abduction and murder of prominent human rights activist Natalia Estemirova.
Estemirova, 51 at the time of her killing in 2009, worked for the human rights organisation Memorial in the Chechen capital Grozny and documented extrajudicial killings, disappearances and abuses by law enforcement agencies.
She was kidnapped in July 2009 and shot in the head and chest. Her body was recovered in the neighbouring region of Ingushetia.
In a ruling published on Tuesday, the ECHR said there was not enough evidence to conclude that Estemirova had been kidnapped by state agents as her sister, who brought the lawsuit, had alleged.
The court said that evidence in the case did however "cast doubt on the thoroughness of the investigation" and that the government had also failed to submit the entire investigative file for the court's assessment.
"The Court concludes that the authorities failed to investigate effectively the abduction and killing of Natalia Estemirova," the court said.
There was no immediate response to the ruling from the Russian authorities.
In 2010, Russian investigators charged militant Alkhazur Bashayev with Estemirova's abduction and murder. His whereabouts remain unknown.
Critics and activists say Moscow has turned a blind eye to right abuses in Chechnya, where it fought two wars against separatists after the 1991 break-up of the Soviet Union.
The region is ruled by Ramzan Kadyrov, whose administration receives a wide degree of autonomy and subsidies in return for loyalty to the Kremlin.
Rights groups and Western governments say Chechen authorities repress political opponents, discriminate against women and harshly persecute sexual minorities, allegations Chechnya's leadership denies.
(Reporting by Gabrielle Tétrault-Farber; Editing by Andrew Osborn)
