The three suspects, including two chemistry students at a Moscow institute, were arrested after an explosive device detonated at Cherkizovsky market in northeastern Moscow on August 21, killing 11 people and injuring at least 49.
And police chief Vladimir Pronin said the trio had been implicated in other attacks. "We have the proof that they have set off at least eight bombs," he said, "Thankfully, there were no fatalities, but people were hurt."
He declined to give any other details in the interests of the investigation.
The alleged market bombers were detained on the day of the attack and charged with the premeditated murder of two or more people on grounds of ethnic and racial hatred.
They later confessed they were motivated by racial hatred, prosecutors said.
Racist sentiments have spread among young Russians in recent years, resulting in a growing number of attacks on dark-skinned foreigners. Human rights groups have expressed alarm as police and courts continue to treat such cases as hooliganism, rather than ethnically motivated crimes.
