BBC East reporter Maria Veronese at Norwich airport
A BBC East investigation has uncovered security issues at one of the UK's regional airports.
The undercover team exposed security loopholes by driving undetected into the restricted area of Norwich International Airport.
Security is supposed to be tight because of a "severe" threat of terrorism in the UK.
The team was able to pass undetected through a security checkpoint past three barriers on two separate days.
They walked to where aircraft are manoeuvred and serviced and spent 45 minutes inside without being challenged.
The team was also able to drive in the vicinity of the taxiing runway and stand next to jet fuel tanks beside one of the hangars.
Norwich International has expanded rapidly in recent years and handles 800,000 passengers a year.
But last year it made a loss of more than £400,000.
Major airlines, such as Air France, and KLM, use the airport to service some of their planes and it is also a terminal for helicopter flights to offshore gas rigs.
Our investigation found that at certain times of the day, vehicles could come and go freely into the restricted area of the airport because the main security checkpoint was left unmanned.
Some of the barriers were left in the upright position and at one point over Easter the barrier was stuck open.
On two occasions a reporter drove a car into Norwich airport's restricted area
Entry through this gate is supposed to be controlled, but it has become common practice for shift workers to tailgate each other through the security gate without stopping at the intercom.
In January the Department of Transport introduced compulsory training for airside staff, including how to spot suspicious behaviour.
But reporter Maria Veronese and producer Julian Sturdy with cameras and a backpack were able to walk by workers.
They were able to approach aircraft and film in the airport manoeuvring area - 20 minutes before passengers boarded a KLM flight to Amsterdam.
The BBC team made no attempt to get onto planes or interfere with baggage.
Many passengers use the Norwich to Amsterdam hop as the starting point for flights around the world.
Chris Yates is an aviation security analyst, and editor of Jane's Airport Review and has been involved in post-11 September security reviews around the world.
He said: "In my opinion it is entirely pointless stuffing airport terminals full of very expensive shiny screening machines to prevent nasty things happening when the back door is left wide open for anyone to walk into the supposedly secure airside, get up close and personal with aircraft.
"The consequence of such lax security doesn't bear thinking about in this day and age."
Chris Yates said some airports paid "lip service" to security
Under regulations, any airport serving international aviation must prevent unauthorised access to aircraft.
"There are many airports in this country where lip service is paid to this issue. In my view the UK is in breach of its international obligations by failing to ensure its airports meet the requirements," said Mr Yates.
Group Four Securicor (G4S) has the contract to secure the airport and is in charge of controlling access to aircraft and vehicle access into the restricted zone.
A spokesperson for G4S Aviation Services (UK): said: "We can confirm that G4S Aviation services (UK) provides security at Norwich Airport.
"However, the company is not contracted to provide a permanent security presence.
"The alleged security breach identified by the BBC occurred at a time when G4S was not contracted to provide security. Any concerns arising from the alleged incident are a matter for the operators of Norwich Airport.
"G4S Aviation Services (UK) operates to the highest industry standards and will continue to ensure that these high standards are maintained."
We have taken immediate action to rectify any shortcomings in our procedures to ensure that similar events do not happen again
Norwich International Airport
The BBC footage was shown to airport authorities before transmission to give them time to close the loophole.
Within hours, security at the main gate had been stepped up.
In a statement the airport said: "Norwich International Airport has been advised by the BBC of an alleged security lapse in relation to access to a controlled area of the airport.
"The airport takes security very seriously and is carrying out a full investigation of the circumstances. We have taken immediate action to rectify any shortcomings in our procedures to ensure that similar events do not happen again.
"The airport is satisfied that there was no risk to passengers travelling to or from the airport on commercial transport flights and that the Restricted Zone has not been breached.
"We have discussed the situation with the Department of Transport and we are satisfied that the action we have taken satisfies the requirements of the UK National Aviation Security Programme.
"Passengers and staff can be reassured that security is our highest priority."
KLM said it was investigating the incident with the airport authorities and added: "Under current regulation, airlines are not responsible for airport security.
"KLM never compromises on the safety and security of its passengers, and in addition to airport security measures KLM always performs its own pre-flight security checks to ensure a safe flight operation."
See the full investigation, and a live interview with the airport manager on Look East tonight BBC1 at 1830 BST.
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