He added that flames "seemed to be coming from the rear or back of the plane."
Bhagavathul said the blaze was "under control within 15 to 20 minutes." He saw at least three fire engines at the scene. Officials said that no injuries were immediately reported.
"The entire top half of the plane is gone," Bhagavathul added.
Emirates confirmed that Flight EK521 from Thiruvananthapuram, India, to Dubai has been "involved in an accident" at the airport at around 12:45 p.m. local time (4:45 a.m. ET). It said that 275 passengers and crew were aboard.
In a statement, the airline added: "Our main priority is now the safety and well-being of all involved."
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Tracking websites identified the aircraft as a Boeing 777-300 that was delivered to the airline in 2003.
Authorities said that passengers had been able to disembark from the burning jet.