An official of the Kenyan National Police Service Commission says 63 police officers including a police spokesman have been fired for "corruption and integrity issues."

Johnstone Kavuludi said Thursday investigations have revealed a hierarchy in the way proceeds of corruption are shared among police officers.

Kenya is vetting all its police officers as part of a reform package the government agreed to undertake after adopting a new constitution in 2010. The aim is to prevent a repeat of the postelection violence that was seen in the country following a flawed presidential poll in December 2007 that left more than 1,000 people dead. Kenya's police force was accused of taking sides during the violence.

The police force is the most corrupt institution in Kenya, according to global anti-corruption watchdog Transparency International.