A NORTH-EAST man walked unchallenged onto two aeroplanes carrying a potentially deadly flick-knife, it emerged last night.

The incident has prompted police in the region to express concerns about the "embarrassing" security arrangements at the foreign airports involved in the breaches.

The man had the weapon in his hand luggage, and a search of his checked-in bags revealed a further cache of four more illegal blades.

Officers at Durham-Tees Valley Airport have been praised after they apprehended the man, who was returning to the region from a trip to Thailand.

Because of their vigilance, a security warning has been sent to other airports about the flick-knives, which are disguised as cigarette lighters.

Before he was apprehended on Monday, the man had got on a flight in Thailand and then another plane at Schiphol Airport, in Amsterdam, in the Netherlands.

Police say the 2in blades, with a serrated top edge, were more than capable of killing somebody. Each of the weapons has the word "knife" printed on the handle.

A spokesman for Durham Police said: "There has been a double security breach here.

"It shouldn't have been in the cabin if it had been examined in Thailand and Schiphol.

"From our point of view, there's some serious questions need to be raised about security at these airports They should be seriously embarrassed about this discovery."

He added: "The vigilance of the officers at Durham-Tees Valley Airport is to be commended.

"As a result of their alarm, security officers at airports around the country have been warned about what they found."

Following the detection of the five flick-knives, the passenger - who is in his mid-40s and lives in Middlesbrough - was arrested on suspicion of possessing an offensive weapon.

The suspect, who is originally from Sunderland and has not been named by police, is due to answer bail at Darlington police station today.

Detective Superintendent Neil Malkin said: "These weapons were found as a result of the vigilance of the police officers on duty at the airport, and underlines our determination to check out and assess the threat that any items might pose as we try to make our travel as safe as possible.

"It is absolute folly for anyone to try to bring weapons of this sort into or out of the country, and those who try face immediate arrest and the prospect of any prosecution that might follow.