Mukhamedjanov also said the police had arrested a sixth person, the suspected mastermind behind the killing of Altynbek Sarsenbaev.
Mukhamedjanov said that the "organizer" had paid $25,000 for Sarsenbaev to be kidnapped and delivered "to an agreed location," RFE/RL's Kazakh Service reports.
The minister added that, at the invitation of the Kazakh authorities, an agent from the U.S. Federal Bureau of Investigation (FBI) has arrived to Almaty to assist in the investigation.
The body of Sarsenbaev, the co-chair of the Naghyz Ak Zhol (True Bright Path) party, was found along with those of his bodyguard and a driver on the outskirts of Almaty on 13 February. They had been shot.
Opposition figures suspect the government had a role in the killing, a charge rejected by the Kazakh authorities.
Sarsenbaev was the second prominent opposition figure to be shot dead in recent months.
RFE/RL Central Asia Report
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