WASHINGTON, March 16: Some Guantanamo Bay prisoners may have been shackled and chained en route to the US prison facility in Cuba, says Secretary of State Colin Powell.

In a television interview released by the State Department on Tuesday, Mr Powell said such restrictions were necessary to ensure the safety of the plane used to transport the prisoners.

Most of the estimated 650 prisoners were captured in Afghanistan and later brought to Guantanamo Bay. The interviewer-Sir Trevor McDonald of Britain's 'Tonight with Trevor McDonald'- said he had interviewed a recently released prisoner who reported the detainees were shackled and hooded on their way to Guantanamo Bay.

"Well, I'm sure that as they were transported, for the safety of the people on the airplane they were probably restrained in some way," said Mr Powell. "But I'm sure it was done in a manner that would not be unknown to any police organization in the world that is moving a group of individuals from one place to another." "But chained to their seats, shackled and hooded?" The interviewer asked.

"If you're in an airplane, I think that's not an unwise thing to do. If you're on a long plane ride and you're in the air, I think it's wise to keep people restrained so that there is no difficulty aboard the plane for the safety of all aboard the plane," Mr Powell replied.