NEW DELHI (Oct 31): AirAsia India is investigating certain former employees over irregular personal expense claims, the aviation joint venture of Tata Sons and Malaysian airline AirAsia Bhd said in a statement on Monday.

The announcement follows a letter sent last week by the ousted chairman of Tata Sons, which owns 49% of AirAsia India, in which Cyrus Mistry said board members were aware of "ethical concerns" with respect to certain transactions.

He said a forensic investigation had found "fraudulent transactions" of 220 million rupees (US$3.29 million) involving "non-existent parties".

That letter prepared the ground for a "probe into the allegation of mismanagement of funds," said an official at the India's financial crime fighting agency Enforcement Directorate.

AirAsia India said that together with parent AirAsia and Tata Sons, it would investigate allegations of impropriety and misappropriation.

"The three entities do not approve of any unethical practices and will take very stern action against the perpetrators at all levels of the organisation," the company said.