According to local media reports, police in Kazakhstan murdered "dozens" of demonstrators who attempted to attack administrative buildings overnight in the country's largest city Almaty.

"Last night, extremist forces attempted to attack administrative buildings, the Almaty city police department, and local police commissariats," Interfax-Kazakhstan, TASS, and Ria Novosti news agencies said.

"Dozens of attackers have been apprehended," he said, adding that police were checking their identities.

According to local media reports, at least eight law enforcement officers have been murdered, and 317 have been injured in the violence.

Long regarded as one of Central Asia's most stable former Soviet republics, energy-rich Kazakhstan faces its worst crisis in decades after demonstrators unhappy about soaring fuel costs stormed government buildings.

A military alliance led by Russia announced it would send peacekeeping forces to the country to "stabilize" it, blaming the large protests on "external interference."