Iraqi fighter planes have shot down a US unmanned surveillance drone over southern Iraq.

With God's help... it was shot down in a delicate and planned operation Iraqi statement

A senior official with US Central Command, quoted by the Associated Press, said the Predator drone was on a reconnaissance mission when the Iraqi jets infiltrated the southern no-fly zone and shot it down.

The drone's controllers then lost contact with it, the official said.

The Iraqi military confirmed the plane was shot down at 1535 (1235GMT) on Monday, saying the drone had breached Iraqi airspace.

"With God's help, and with the will of the men of our heroic air defence forces and brave sky eagles, it was shot down in a delicate and planned operation," the Iraqi statement said.

Speaking at a Pentagon briefing, the Chairman of the US Joint Chiefs of Staff, General Richard Myers, said the drone was "fired on by aircraft and is assumed lost".

"I don't see it as an escalation," he added, saying Iraqi forces "attempt to shoot down all our aircraft that fly over northern and southern Iraq".

No-fly zones

US and British warplanes patrol two no-fly zones in Iraq, which were set up after the 1991 Gulf War to protect Kurds in the north and Shia Muslims in the south.

Iraq does not recognise the zones and its air defences regularly open fire at allied planes. Iraqi aircraft are barred from the zones.

At least two other drones have been shot down over the no-fly zones in the past two years.

"This action is the latest chapter in a lengthy list of hostile acts by the Iraqi regime," said Jim Wilkinson, a Central Command spokesman.

The US says Iraqi firing at Western jets is a direct violation of UN resolutions on disarming Iraq.

Four of the drones, a ground control station and a satellite link cost $40m.

Drone's mission

The RQ-1 Predator spy plane is part of a highly sophisticated, multi-million-dollar intelligence gathering and targeting system.

It was developed in the 1990s for use in what the US describes as "moderate-risk environments" - where enemy air defences remain a threat, or in areas which may have been contaminated by chemical or biological weapons.

With its bulbous nose, the aircraft has a wingspan of 14.6 metres (48.7 feet), weighs 430 kilograms (950 pounds) empty and 1,020kg (2,250 lbs) when fully equipped for reconnaissance, surveillance or target-finding missions.

Each Predator is fitted with:

• colour nose camera - generally used by the operator for flight control
• daylight TV camera
• infra-red camera for poor light/night missions
• radar to scan through smoke, clouds or haze.

Predators can remain airborne for nearly 24 hours at a time.

Cruising at up to 7,500m (25,000ft), the planes have a maximum speed of 225km/h (140mph) and a range of 735km.

Their relatively slow speed, however, makes them vulnerable to missiles and anti-aircraft gunfire.