A FEARLESS four-legged recruit joined US Special Forces as they stormed Osama Bin Laden's secret lair.

The explosive-sniffing dog was strapped to an assault team member as they took on one of their greatest challenges to date.

He was part of the operation in which the elite US Navy Seals lowered themselves down ropes from three Black Hawk helicopters into the terrorist supremo's hideout in the town of Abbottabad, Pakistan, on Sunday.

The world's most wanted man, 54, was shot dead by a Special Forces marksman during the raid.

Heavily armoured hounds — equipped with infrared night-sight cameras — have been used in the past by the top-secret unit.