FOREIGN secretary and Blackburn MP Jack Straw today called for an investigation after knives sold by a local company were allegedly smuggled on to two aeroplanes.

A stainless steel miniature cleaver which folds up to look like a credit card, a four-inch knife disguised as a comb and a knife blade hidden inside a pen were all reportedly taken onto two domestic British Airways flights between Heathrow and Manchester.

All three items are advertised for sale on the Spytech UK internet website which asks people to send their orders to a Blackburn Post Office Box number.

The alleged breaches in security at Manchester and Heathrow airports were highlighted in a Sunday newspaper and were today being looked at by the British Airports Authority, British Airways and the Department of Transport.

The newspaper's report comes just a week after a British man was caught trying to detonate an explosive device in his shoe while on board a transatlantic flight from France.

Mr Straw expressed concern that potentially dangerous items which could disguised and taken on to aeroplanes were being sold quite legally. He vowed to investigate the allegations and said: "This is very worrying.

"I am concerned about this and will be looking into what happened. I am sure an investigation will be launched by Transport Secretary Steven Byers and I shall be looking at that with interest."

Manchester Airport has so far only said that passengers are subject to UK-standard checks, while the British Airport Authority, which runs Heathrow Airport, said it was investigating the claims, as is British Airways.

The Spytech UK website offers a variety of instruments for sale. Several items on the site claimed to be 'undetectable,' and many of the products, including the comb and the miniature cleaver were described as being for novelty use only.

The advertised items included a £9.95 Stealth Defence Comb, a four-inch dagger made of toughened nylon disguised to look like a comb. The site warned that it could be a lethal weapon.

Today, there was no answer at telephone number given for the firm on its website.

But the newspaper report which highlighted the alleged security breaches quoted the Blackburn man believed to be behind the firm as saying: "Anything can be misused. If airport security did their bit these things would have been detected."

Security at Manchester Aiport was stepped up after the September 11 attacks in America.

British Airways confirmed it will be launching its own investigation into the claims.

A spokesman said: "We are very concerned to hear about this and will be talking to the Government to find what can be done to prevent such items getting on board aircraft."

The Department of Transport, Local Government and the Regions (DTLR) said it would also be investigating the allegations.