British holidaymakers are facing travel chaos at Heathrow after a cyber attack disrupted check-in and boarding systems for several major European airports.

Passengers at the UK's largest airport are experiencing three hour long queues this morning after hackers targeted Collins Aerospace, which provides services for multiple airlines globally, on Friday night.

The company is 'experiencing a technical issue which may cause delays for departing passengers'. Although the attack 'is limited to electronic customer check-in and baggage drop and can be mitigated with manual check-in operations', it added.

The timing of the attack coincides with recent Russian incursions into NATO territories, the latest taking place just hours ago when three fighter jets entered neighbouring Estonia in a 'reckless' and 'brazen' attempt to intimidate the Baltic state.

Heathrow has warned of delays and advised customers to check their flight status with their airline before travelling, while a number of departures were also cancelled.