Abu Mahdi al-Muhandis, the second-in-command of the volunteer anti-terror fighters, said at a press conference on Sunday: "We have complete information and documents that show the US embassy and consulate in the country caused the Basra unrest”.

Muhandis held Washington responsible for the Basra unrest, saying it was actually meant to sow discord among different Iraqi political parties and movements.

He also said they will respond to the Basra incidents and stressed that the Iraqis would never engage in another civil war.

Basra has been shaken by protests since Tuesday, the latest in a wave of demonstrations since early July. 

The protests turned violent on Friday when a group of masked assailants raided government buildings and offices of political parties and set them ablaze. The Iranian consulate was among the premises attacked.