Staring glumly at his shiny green Yamaha R6, Ali Samir sighs in frustration as he misses another day roaring through Baghdad on one wheel, racing fellow bikers. After a surge of killings in the city by gunmen on motorcycles, the authorities have cracked down on bikers and begun confiscating their only means of transport.

Last month the Ministry of Defence ordered soldiers to stop riders after a series of motorbike murders rocked the Iraqi capital.

“After the crimes at the end of Ramadan, we received orders to stop and arrest the driver of motorcycles, the big ones, because we believe criminals are starting to use them to kill officials from the Defence and Interior ministries,” Lieutenant Ali, an army officer, said.

The Defence Ministry had confiscated more than 1,000 machines, he added, though scooters and bikes with small engines have so far been exempted.

Most bikers in Iraq have no licence or registration papers, having bought their expensive toys in the chaos that followed the invasion. If they are caught without valid documents, they will now lose their machines.

Ali, 23, is one of those who dare not take a spin on the streets. “I am really disappointed,” the mechanic said. “I feel as though I have lost a shoe.”

The security measures have taken the fun out of Friday, the start of the weekend in Iraq, for Ali, his brother Mohammed and their 20-strong gang of bikers, who call themselves “The Monsters”.

“Usually we spend the weekend under the Jadariya Bridge doing stunts and having races,” Mohammed, 27, also a mechanic, said. On Friday nights the city usually buzzes with the roar of motorbike engines but last night Baghdad was silent.

US and Iraqi officials anticipate a rise in targeted killings in the run-up to provincial elections early next year and are deeply concerned by the new method of attack. An officer told how two soldiers at his checkpoint were recently killed by a couple of men on motorbikes.

“We couldn't hear them because they used a silencer on their guns. These weapons are very dangerous, especially when the gunman can make a quick getaway on his motorbike,” the captain said. “That is why the leaders in the Baghdad operation centre decided to ban motorcycles in the street.”

Mohammed, who has been riding motorbikes for nine years, and Ali, who has four years' experience under his belt, bear the scars of adrenalin junkies. Both have been maimed by accidents while perfecting their biking skills, which include riding standing on the seat, doing wheelies and racing at 160mph (260km/h).

“I would like to take part in competitions overseas,” said Ali, who has stitches in his head and a scar on his right leg after smacking into a BMW two years ago. Mohammed, who has a jagged scar on his chin from falling off his 1980s Honda CBR, just wants to buy a bigger, better set of wheels. “Unfortunately, it is too expensive at the moment,” he said.

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