MoS exposes airport security farce: Deadlier knives than used on 9/11 sold in duty free Penknives are on open sale in duty-free section at Swiss airport Expert says he would not have been able to board UK flight with the blades On U.S. flights all types of blades, even penknives, are banned By Simon Murphy Major security concerns have been raised after a Mail on Sunday reporter boarded a British Airways flight to London carrying five knives - bought in an air-side duty free shop - with blades longer than those used by the 9/11 hijackers. He walked unchecked on to the packed plane after buying the potentially lethal £20 Swiss Army knives at Zurich airport, Switzerland. The knives are on open sale, despite similar ones being used in a plane hijack attempt only two years ago. The startling revelation poses a massive question mark over the disparity of security checks at airports. Blade runner: Mail on Sunday reporter Simon Murphy brandishes the lethal blades in the aeroplane toilet after smuggling them aboard the British Airways flight from Zurich, Switzerland, to London At British airports, passengers face lengthy queues at security checkpoints. They are made to discard sharp and bladed objects, even ordinary scissors, and liquids over 100ml, including suncream. Officially, EU regulations allow passengers to travel with bladed items no longer than 6cm - the Swiss Army knife is the same length - but an aviation security expert said people would not be able to board flights in the UK if carrying the knives. Last night, Zurich airport and British Airways insisted they were operating within EU regulations. But critics said rules that can prevent mothers carrying baby milk on board yet allow knives to be carried unchecked were putting passengers in danger. On US flights, all types of blades, including Swiss Army knives, are banned. In June, the US transport safety authority scrapped a plan to allow some small pocket knives on flights after a public outcry. Tory MP Nick de Bois said: "We need to change the rules. You can't legislate for the state of mind of the individual carrying the knife so why put the temptation in front of someone? A 6cm toughened blade, which you get in a Swiss Army knife, could be lethal in the wrong hands. People will find it utterly incomprehensible that you can buy knives before getting on planes. Disparity: EU regulations allow passengers to travel with bladed items no longer than 6cm ¿ the length of the Swiss Army knives ¿ but a security expert said people would not be able to board UK flights carrying the knives After going through security, our reporter made two trips to the Victorinox store, which opened in March, and purchased the knives. The shop, yards from a police room, offers an array of knives and even sells knife-sharpeners. Without even being asked for a boarding pass or passport, our reporter bought three knives on the first visit and two more on the second. Priced between £20 and £27, the knives did not come in protective packaging. Afterwards, our reporter simply walked through to Departures, even passing under a sign at the departure gate which showed a Swiss Army knife with a red cross over it. He then travelled on a packed BA flight to Heathrow last Wednesday - with more than 120 people on board including small children. During the flight, our reporter posed for pictures with the blade of one of the knives extended. Danger: After going through security, our reporter made two trips to the Victorinox store, which opened in March, and purchased the knives. The shop offers an array of knives and even sells knife-sharpeners Chris Yates, an aviation security expert, said: "It seems ludicrous that Leeds Bradford Airport stopped a child from carrying a toy gun on a plane a few weeks ago because it looked threatening, when that child could have had several knives on their person for mummy and daddy to use aboard the plane. There is wide disparity with what goes on at airports. If someone turned up at Heathrow with these knives, there'd be some pretty stiff questions and the likelihood is those items would either be confiscated or put into the hold. Mr Yates said that since the 9/11 attacks, the door from the passenger cabin to the flight deck are locked but occasionally opened to provide refreshments to the crew. He explained: "If you're sitting in the front, you can see when that door is open and it doesn't take an Einstein to work out you can be through there in a few seconds with a knife out." In April 2011, Kazakh diplomat Valery Tolmachev tried to hijack a flight from Paris to Rome. The 131 passengers on the Alitalia flight looked on in terror as Tolmachev held a Swiss Army knife to the throat of a female air stewardess, demanding to divert to Tripoli. Disaster was averted only after flight attendants and passengers overpowered the hijacker. The 9/11 hijackers used box cutters which can have blades shorter than Swiss Army knives. Multi-purpose: Victorinox Swiss Army penknives are armed with an array of potentially lethal blades A BA spokesman said: "Security regulations are set by government bodies such as the European Union. We abide by such regulations. A Department for Transport spokesman said: "We are assured by Swiss authorities that all pocket knives sold at their airports comply with existing rules, which allow knives with short blades, of 6cm or less, to be carried in hand luggage." A Zurich airport spokeswoman said: "Swiss Army knives with a blade of 6cm or less are allowed. It doesn't matter if you buy the knife or knives before or after the security checkpoint, neither does the quantity, as long as the blade is 6cm or less in length.