New Delhi, Sep 2 - Prime Minister Manmohan Singh and Congress President Sonia Gandhi Wednesday expressed concern over the reported disappearance of a helicopter carrying Andhra Pradesh Chief Minister Y.S. Rajasekhara Reddy after it encountered inclement weather in the interior areas of the state.

Both were in close touch with the Andhra chief minister's office and promised all help from the centre.

Six Indian Air Force (IAF) helicopters were despatched in the search mission.