ALMATY (Reuters) - Kazakhstan's state security service has detained President Nursultan Nazarbayev's former deputy chief of staff on charges of illegally collecting and sharing classified information, it said on Monday.

Baglan Mailybayev, 41, was detained along with one of his ex-subordinates on Jan. 12, the National Security Committee said, the same day he was sacked from his post.

(Reporting by Olzhas Auyezov; editing by Polina Devitt)