India's aviation regulator DGCA has formed a three-member team to conduct a "fact-finding enquiry" into IndiGo recently barring a specially-abled child from boarding a flight at the Ranchi airport as he was in a "state of panic", officials said on Monday.

"They will visit Ranchi and Hyderabad (place of stay of the family concerned) and collect appropriate evidence within one week from today. Based on the outcome of the said enquiry, further action shall entail," the Directorate General of Civil Aviation (DGCA) noted in a statement.

IndiGo CEO Ronojoy Dutta expressed regret on Monday over the incident and offered to buy an electric wheelchair for the specially-abled child.

Dutta said the airline staff took the best possible decision under difficult circumstances.

Aviation Minister Jyotiraditya Scindia said on Twitter that no human being should have to go through this and he himself is investigating the Ranchi incident.

Meanwhile, the National Commission for Protection of Child Rights (NCPCR) has asked the Jharkhand police to lodge an FIR against IndiGo as there was a prima facie violation of section 7 of the Rights of Persons with Disabilities Act, which is cognisable in nature.

NCPCR Chairperson Priyank Kanoongo has also asked the Directorate General of Civil Aviation (DGCA) to initiate an inquiry in the matter and take necessary action against the airline and its manager.

The incident came to light after other passengers highlighted it on social media on Sunday.

DGCA chief Arun Kumar told PTI on Sunday that the aviation regulator has sought a report from IndiGo on the matter.

The DGCA is probing the incident and will take appropriate action, he said.

In a statement, Dutta said, "We recognise too well that parents who dedicate their lives to the caring of physically-challenged persons are the true heroes of our society.

"We offer our sincere regrets to the affected family for the unfortunate experience and as a small token of our appreciation of their lifelong dedication, would like to offer to purchase an electric wheelchair for their son."

As the boy was prohibited from boarding the airline's Ranchi-Hyderabad flight on Saturday, his parents -- who were accompanying him -- also decided not to enter the plane.

Dutta said, "Having reviewed all aspects of this incident, we as an organisation are of the view that we made the best possible decision under difficult circumstances."

"Throughout the check-in and boarding process, our intent of course was to carry the family. However, at the boarding area, the teenager was visibly in panic," he added.

While providing courteous and compassionate service to the customers is of paramount importance to the airline, the airport staff, in line with the safety guidelines, were forced to make a difficult decision as to whether this commotion would carry forward aboard the aircraft, the IndiGo CEO stated.

"All of us at IndiGo are truly distressed by this particular incident," he said.

Since April, the airline has carried over 75,000 specially-abled passengers in its flights and its crew and airport staff are trained to serve such passengers sensitively, Dutta added.

According to DGCA regulations issued in 2017, passengers who are likely to be unruly and disruptive must be carefully monitored and if deemed to pose a threat to the safety and security of a flight, fellow passengers or the staff on board the plane, they should be refused embarkation.

"Airline shall establish mechanism to detect and report unruly passenger behaviour at check-in, in the lounges and at the boarding gate in order to prevent such passengers from boarding," the regulations said.

In a statement issued on Sunday, IndiGo said in "view of the safety of passengers, a specially-abled child could not board the flight with his family on May 7, as he was in a state of panic".

The ground staff waited for him to calm down till the last minute but to no avail, it added.

The airline made the family comfortable by putting them up in a hotel and they flew the next morning to their destination, it said.

A passenger, Manisha Gupta, posted about the incident in detail on LinkedIn on Sunday.

She said the adolescent with special needs was in great discomfort at the Ranchi airport on Saturday.

"The exhaustion of the drive to the airport and then the stress of security check has sent him into the throes of hunger, thirst, anxiety and confusion. His parents obviously knew how to handle his meltdown -- with patience, cajoling, stern-ness, many hugs," she wrote.

By the time the boarding began, the child was fed and given his medicines, Gupta noted.

He seemed ready except for some big displays of general teenage assertiveness, she said.

"Then we witnessed the full display of brute authority and power. The IndiGo staff declared that the child would not be allowed to take the flight because he was a risk to other passengers.

"The IndiGo manager also said something on lines of 'behaviours such as this, and that of drunk passengers, deems them unfit to travel'," Gupta wrote.

The other passengers opposed him resolutely and demanded that the child and his parents board the flight as soon as possible, she informed.

However, the IndiGo staff did not change their decision of barring the child from taking the flight, Gupta said.