Police say an official at India's federal aviation authority has been arrested in a widening investigation of corruption in awarding flying licenses to airline pilots.

Police spokesman Rajan Bhagat said Saturday the official, a pilot and two other men arrested in New Delhi were involved with a flying school in western India that issued fake certificates of training flights to its students.

Four airline pilots already had been arrested in the past two weeks for having fake certificates that allowed them to get licenses.

India's aviation industry has grown rapidly with the country's economy in recent years, and airlines have struggled to train enough qualified pilots for the jobs.