Delta finally admits there was a 'small fire' at data center in Atlanta Monday as airline headaches move into day four 

• Delta Air Lines says a 'small fire' at its data center caused computer outage that cancelled over 2,100 flights
• CEO Ed Bastian said a piece of electrical component at its Atlanta headquarters failed 
• That led to a shutdown of the transformer providing power to the airline's data center and not all the servers were connected to backup power 
• Delta won't detail the extent of that fire and the damage it caused 
• They also won't say how the fire was extinguished or if the means of putting it out damaged other electrical equipment or the servers
• Thursday there were at least 30 flight cancellations and 300 other delays

A 'small fire' at Delta Air Lines' data center in Atlanta caused the massive computer outage that left thousands of people stranded due to flight cancellations.

CEO Ed Bastian told The Associated Press on Wednesday that the problems began early Monday morning when a piece of electrical component at its Atlanta headquarters failed. 

That led to a shutdown of the transformer providing power to the airline's data center. 

The system moved to backup power but not all of the servers were connected to that source, which caused the cascading problem.

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But that initial failure also caused a fire. The airline is refusing to detail the extent of that fire — and the damage it caused.

'The equipment failure sparked a small fire. It was put out immediately and there was no need to call the fire department,' Delta spokesman Trebor Banstetter said via email Thursday.

The airline would not say how the fire was extinguished or if the means of putting it out damaged any other electrical equipment or any of the computer servers. 

Delta has canceled more than 2,100 flights so far this week, the most of them happening Monday and Tuesday. 

But Thursday morning still had some headaches for travelers, with FlightStats.com reporting at least 30 Delta flight cancellations and nearly 300 other delays. 

Some were due to the computer problems and others were due to bad weather, the airline said.

Bastian, on Wednesday, said that Delta knew it had to make technology upgrades 'but we did not believe, by any means, that we had this type of vulnerability' regarding its flight operations and reservations systems.

Delta takes pride in having one of the best on-time records and rarely canceling flights. 

Bastian, who took over as CEO in May, said this week's problems do not reflect his airline's long-time track record or what he foresees for the future.

'We're going to do everything we can to make certain it does not ever happen again,' he said.