New Delhi, Sep 2 - The Indian Air Force (IAF) Wednesday afternoon joined the search for a missing helicopter carrying Andhra Pradesh Chief Minister Y.S. Rajasekhara Reddy, pressing four choppers into service, an official said.

'We have deployed four helicopters for the rescue mission. They include two Chetaks, besides one Mi-8 and one ALH (advanced light helicopter),' an IAF spokesman here said.

Addressing a press conference in Hyderabad, Andhra Pradesh Chief Secretary Ramakant Reddy said the chief minister remains untraced after his helicopter went missing amid bad weather Wednesday morning.

He said the government had not been in touch with the chief minister since 9.