Russian federal investigators say they are looking into the deaths of a former police officer and five of his family members who were found in the central Russian town of Syzran during the weekend.
Russian media reports say the bodies of Andrei Gosht and his relatives were discovered at their home in Syzran on April 24, about 1,000 kilometers southeast of Moscow.
Authorities said they appear to have died from blunt-force trauma.
Reports say Gosht's 7-year-old niece was the only relative who survived.
She was hospitalized with heavy trauma injuries.
The federal Investigative Committee's Vladimir Markin told Interfax that the brutality and calculated nature of the murders resembled the 2010 killings of 12 people at a village in Russia's southern Krasnodar region.
Investigators later determined that those killings had been carried out by a criminal gang.