The West Bengal government on Saturday sought a report from the Directorate General of Civil Aviation (DGCA) on Chief Minister Mamata Banerjee's aircraft encountering mid-air turbulence while returning from Varanasi, a top bureaucrat said.

The state government also wanted to know from the DGCA whether the route taken by the plane in which the chief minister returned to the city from Varanasi on Friday evening had been granted prior permission, he said.

Mamata was returning from Uttar Pradesh after campaigning for the Samajwadi party. When contacted, an official of the DGCA said that they have already started working on the report. "We conduct investigations in all such cases and accord priorities where VVIPs are involved. We have already started working on preparing our report in this connection," he told PTI.

On Friday evening, the chartered flight carrying Mamata from Varanasi airport to the city hit an air pocket causing the plane to rock violently.

The pilot managed to steer the plane out of the air pocket and land it safely in Netaji Subhas Chandra International Airport here though Mamata suffered a back injury caused by the steep climb-down the flight had to make to cope with the turbulence. Mamata was on board a Dassault Falcon 2000, which is a 10.3-tonne lightweight plane with a capacity of carrying a maximum of 19 people, including two flight attendants.

Meanwhile, the Trinamul Congress on Saturday demanded a high-level probe into the incident of the Falcon aircraft, hired by the state government for the chief minister, encountering a spot of air turbulence.

TMC national spokesperson and veteran Rajya Sabha MP Sukhendu Sekhar Roy told PTI that it was a serious matter and posed a threat to the chief minister.

"There should be a high-level probe by the DGCA covering all aspects from the aviation point of view. There should also be another probe by the Centre from the security aspect as the chief minister is entitled to Z category security," he said.

Roy said the party wanted to know the reason why the aircraft of the chief minister had faced similar situations in past during her flight from Patna to Calcutta and from Bagdogra to Calcutta.

The probe should cover all these aspects as well, the TMC national spokesperson said.