A BBC investigation has revealed what the corporation claims are "shocking" security lapses at Manchester Airport.

An undercover reporter working as an aviation security officer for the BBC One Whistleblower series was encouraged to flout Department for Transport rules on bag searches, the BBC said.

It said she also found aircraft left open and unattended overnight and that staff knowingly used faulty metal detectors.

A Manchester Airport spokesman said: "We take any allegations of shortcomings extremely serious and any breaches in procedure are rectified immediately."

Journalist Michelle Cox spent ten weeks working at the airport.

Programme makers said on one occasion around a thousand passengers passed through the airport from Pakistan but only three random bag searches took place.

"Michelle was told by colleagues to exaggerate the figures, with one workmate openly declaring, `We cheat'," a statement said.

"Michelle also discovered planes left open and unattended on the tarmac overnight with easy access provided by the steps, which had been left attached, contrary to security rules."

The reporter was also able to gain access to one of the planes and film undisturbed, the programme said.

The BBC also claims the film will show a metal detector failing to sound when a knife and gun were passed through it as part of a test.

It said: "The detector failed to go off on a number of occasions and was shut down.

"The second detector in the area was tested with a large pair of scissors and also failed to go off on a number of occasions.

"This one was not shut down and staff continued to allow approaching passengers through security using the unreliable machine."

Security team leaders are also alleged to have tipped off colleagues about covert DfT inspectors, phoning their physical descriptions through to colleagues.