The abduction appeared to be part of the growing sectarian violence between rival Sunni and Shia Muslim groups which has left hundreds dead in mixed neighbourhoods in and around Baghdad this year.

The attack occurred near the city’s bus stations, when a convoy of a dozen pick-up trucks, bearing the camouflage markings of the Police Commando unit, sealed off a corner of the Salihiya area popular with travel agents for those going by road to Jordan, Lebanon and Syria.

“It took them about five minutes to take people away. One, two, three, four — one after another,” said Hamza Ali, an eyewitness. “Those abducted appeared to have been taken at random from the street and included vendors, workmen and even some Syrian nationals.

“They took people randomly,” said a shop owner. “They grabbed a father and his two children but left the mother on the street shouting.”

There were fears that the raid may have been in retaliation for a grisly killing on Sunday, north of the city, when gunmen pulled over two minivans carrying teenage students. They forced the passengers off, separated Sunnis from Shias and executed 21 Shias who were first made to lie face down on the ground.

In the past Shia militias supported by Iran have been accused of kidnapping, torturing and executing Sunnis. There is also evidence that serving members of the security forces have been implicated.

Major General Adnan Thabet, the chief of the Iraqi national police, denied that any of his officers was involved. But the raid will erode confidence in the new government of Nouri al-Maliki. From Ali Hamdani

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