Belarus took in Bakiyev last week after he fled in the aftermath of a bloody revolt. Moscow made clear he was not welcome in Russia.
"The former president of Kyrgyzstan, Kurmanbek Bakiyev, has been charged with mass killing," Azimbek Beknazarov, an interim vice premier in charge of security, said in the capital Bishkek. The extradition request would be sent "within days,” he added.
Bakiyev might also be charged with abuse of power in an official capacity, Beknazarov told reporters.
Troops loyal to Bakiyev shot into crowds of protesters on the night of April 7-8. Some protesters were armed and fought back and at least 85 people were killed. Bakiyev has maintained Moscow may have played a role in his overthrow.
Russian security forces detained Kyrgyzstan's former top police official, Moldomusa Kongantiyev, and sent him home on Monday. The extradition signalled strong Russian support for the new administration that came to power after the uprising that started on April 7.
The interim government said Kongantiyev was under arrest and being investigated for his role in the upheaval earlier this month, among other things.
The unrest disrupted flights through a US air base that supports operations in Afghanistan and adds to the strategic significance of the impoverished ex-Soviet state.
Kyrgyzstan's new rulers have struggled to stamp their authority on the predominantly Muslim nation of 5.3 million as rival clans and ethnic groups vie for influence.
