Protesters mark Mubenga death

Mr Mubenga collapsed and died after being restrained by guards from private security firm G4S.

To mark the anniversary of Mr Mubenga's death, campaigners staged a series of demonstrations outside the offices of both G4S and the CPS over what they describe as its "political" decision not to prosecute.

The demonstrations were called by the Stop G4S coalition, No Borders London and the Stop Deportation network.

The three guards involved in the forced deportation were arrested on suspicion of manslaughter after eye witnesses claimed that their use of restraints was "excessive."

But in July the Crown Prosecution Service (CPS) said that the three would not face charges over Mr Mubenga's death.

The former chief inspector of prisons Lord Ramsbotham hit out at the decision at the time, describing it as "perverse."

Following Mr Mubenga's death G4S lost the detainee escorts contract with the UK Border Agency (UKBA) to rival firm Reliance, but the UKBA said that the decision had nothing to do with the incident.

The day of action took place a week after campaigners from across Britain gathered in Sheffield for a "Stop G4S" conference.

The firm has faced numerous allegations of abuse and brutality and has also come in for intense criticism over its role in the Israeli prison system.

It has also been under fire for the part it has played in the privatisation of policing and various other public services.

A spokesperson for Stop G4S said: "G4S should not be allowed to profit from torture and death and get away with it."