A fuel alert forced a SpiceJet plane from Hong Kong to Delhi to make an emergency landing at Varanasi on Sunday morning.

“A Boeing 737 plane of SpiceJet issued a pan-pan call for permission for a priority landing at Varanasi after an engine shut-down,” a government source said. The plane took off from Hong Kong at 7.40 a.m., and was to have landed at New Delhi at 10.50 am.

A pan-pan call is issued when there is a minor emergency that requires assistance, but is not life-threatening.

The airline said the pilot noticed that the fuel supply to one of the engines was low, a problem caused by a glitch in a fuel control valve. “Pilots followed the standard operating procedure and landed safely in Varanasi. The passengers were deplaned normally. On inspection, a fuel control valve (a minor component) was found to have malfunctioned and is being replaced,” the airline said in response to a query.

The airline did not disclose the number of passengers on the aircraft.