Bengaluru: The Congress on Thursday complained to the Karnataka Police that the aircraft in which its party President Rahul Gandhi flew to Hubli in the state earlier in the day suffered a snag mid-air.

"The aircraft on a special flight (VT-AVH) from New Delhi to Hubli suffered serious malfunction and tilted heavily to one side during the course of the flight," a party official and Gandhi's aide Kaushal Vidyarthee said in the complaint.

The complaint, addressed to the state's Director General Neelamani N. Raju, requested the state police chief to "ground" the aircraft at Hubballi and investigate its malfunction.

However, a Hubballi Police official told IANS over phone that no complaint has been received by the local police station on the issue so far.

The complaint letter, also shared by the Congress through its official Twitter handle, however, does not mention the exact make of the aircraft the Congress President flew in and whose it was.

According to the letter, there were a total of three other passengers in the aircraft besides Gandhi and the complainant Vidyarthee -- Rampreet, Rahul Ravi and Special Protection Group officer Rahul Gautam.

Alleging the aircraft's auto-pilot mode was not functional and the aircraft could be landed only after two unsuccessful tries as it was "shaking and making unusual audible sounds", the letter pointed to a possible "intentional tampering" with the aircraft's functioning.

"The technical snags coupled with the failed auto-pilot system raise issues of aviation safety and intentional tampering which endangered the life of the passengers," it added.

Gandhi arrived at Hubballi airport at around 11.25 a.m. on Thursday on a two-day visit to the poll-bound state to launch the party's campaign for the May 12 legislative assembly elections in the coastal region.

In New Delhi, Congress spokesperson Randeep Singh Surjewala said that demanded a thorough investigation into the "serious case of aviation mechanics failure", including the possibility of a "foul play".

"Today Congress President Rahul Gandhi and other passengers were travelling by special flight from Delhi to Hubli. At about 10:45 am, the auto-pilot was lost off the flight. The flight tilted on one side and took a nosedive.

"For a few minutes, this special flight was off-the-radar. There was a lot of shuddering, although the weather outside was normal and sunny. On the third attempt, the flight finally landed at Hubli," he said.

"It was then informed that the auto-pilot had failed, also the radars of the flight had partially failed."

Surjewala also pointed out that usually when an SPG protectee is travelling, the complete details of the pilotsand the aircraft are submitted to the DGCA and the SPG.

"Only when all of these are cleared, then the flight plan is okayed. This is a serious case of aviation mechanics failure.