WASHINGTON, March 16: In its most challenging attempt, the latest test in a US missile defence programme was successful on Friday when a projectile weapon destroyed a mock warhead in space over the Pacific Ocean after accurately choosing the target over three decoys, the Pentagon said.

“Tonight’s test is a major step in our aggressive developmental test programme,” the Pentagon said in a statement.

Out of six tests since 1999, it was the fourth to be successful in US efforts to develop a shield against a missile attack from potentially hostile states such as North Korea, Iran and Iraq.

Russia and China oppose the planned US missile shield, saying it could lead to an arms race to overcome new defences.

“We will continue to pursue this testing regime to achieve a layered approach to missile defence, using different architectures to deter the growing threat of ballistic missiles carrying weapons of mass destruction,” the Pentagon said.

At a cost of more than $100 million, Friday’s test for the first time deployed three inflated balloons in space to see if a test weapon could be diverted from tracking and colliding with a dummy warhead launched westward over the ocean from California. Previous tests had used one decoy balloon.

At 9:41 p.m. EST, 0241 GMT Saturday a projectile weapon fired from Kwajalein Atoll in the Pacific intercepted and destroyed a mock warhead launched from Vandenberg Air Force Base in California, about 4,800 miles (7,700 km) away, Defence Department spokeswoman Cheryl Irwin said.

PRESSING FORWARD: The Pentagon later this year plans to begin a more robust testing programme, which it said has been slowed by the 1972 anti-ballistic missile (ABM) treaty drawn up between the United States and the former Soviet Union.

President George W. Bush on Dec. 13 gave Moscow a formal six-months notice that the United States was withdrawing from the treaty in order to press ahead with more advanced testing that would have violated it.

The president said the Sept 11 attacks on America proved the need to develop ways “to protect our people from future terrorists or rogue state missile attacks” even though hijacked aeroplanes, not missiles, struck the Pentagon and New York City’s World Trade Center, killing more than 3,000 people.

It marked the first time in recent history the United States has abandoned a major international arms treaty.

For three decades, the treaty stood as a bedrock of US-Russian nuclear stability. Moscow says it remains a cornerstone agreement upon which other arms accords rest, while Bush argues it is a Cold War relic.

SPEEDING BALLOON DECOYS: In the test, the mock warhead was lifted into space on a modified Minuteman-booster rocket along with the three balloon decoys.—Reuters