The United States Navy is to stop using the Puerto Rican island of Vieques for military training exercises.

Vieques' 8,000 residents have long objected to the use of their island as a bombing range, especially as depleted uranium (DU) shells have been linked to rocketing cancer rates there.

But local protests intensified - which included people tying themselves to US military installations - after a Puerto Rican security guard was hit by a stray bomb in 1999.

The Bush administration in 2001 pledged to end military activity on the island.

The navy says military training will cease from May and that bombing ranges in Florida as well as a computer simulation training system known as "Virtual Sea" will be used instead.

The US may also close Roosevelt Roads naval station in east Puerto Rico, which is the largest employer on the island, the Associated Press news agency reports.

"Without Vieques there is no way I need the facilities at Roosevelt Roads - none. It's a drain on defence department and taxpayer dollars," Admiral Robert Natter, commander of the Atlantic Fleet, told AP.

The US Congress passed a law in 1941 giving the navy the right to use Vieques, which has also been leased out to other Nato fleets for training.