British Airports Authority (BAA) is investing £23m in a top-secret programme to combat the threat of cyber-terrorism.
BAA said it is more concerned about the threat of an electronic attack by terrorists than any other form of computer attack.
Details of the programme, known as 'Shield', were revealed by BAA group services director Tony Ward at an Economist Conference this week.
"We all know that cyber-crime is on the increase but it is the potential for cyber-terrorism that keeps me awake," he said.
Ward said the UK airports group has invested £23m so far in the multi-year programme to beef up IT security defences against any computer attack by terrorists. "It's a big investment by any means," he said.
A spokesman for BAA refused to divulge further details on Shield for 'operational reasons' but said it is an ongoing programme.