The aviation regulator of India issued a warning notice to SpiceJet, saying the budget carrier had failed to establish its services were safe, efficient and reliable and citing a review from last year that found “poor internal safety oversight and inadequate maintenance actions” by the airline.

The show-cause notice by the Directorate General of Civil Aviation (DGCA) comes after a spate of air safety incidents reported by SpiceJet flights. A review found several incidents since April 1 in which “the aircraft either turned back to its originating station or continued landing to the destination with degraded safety margins”, the DGCA said, asking the airline to explain why action should not be taken against it.

“Even the smallest error hindering safety will be thoroughly investigated and course-corrected,” the civil aviation minister Jyotiraditya Scindia said.

A SpiceJet spokesperson said the company was in receipt of the DGCA notice and will respond within the time it has been given. “We are committed to ensuring a safe operation for our passengers and crew,” he added.

Since May 1, there have been at least nine air safety incidents reported from flights operated by the airline. The latest of these was on Tuesday when pilots of a SpiceJet freighter plane to Chongking returned to Kolkata after the weather radar was found malfunctioning.