The Home Office has asked to see BBC undercover evidence of alleged racism and violence by security staff at an asylum seeker detention centre.
Jason Martin, known as 'Wolfie' was filmed racially abusing immigrants
The evidence was gathered against Global Solutions Ltd staff at Oakington Immigration Reception Centre, near Cambridge, by BBC One's Real Story.
Fifteen employees have been suspended from frontline duties, says GSL.
The Lib Dems urged a review into how such firms were vetted and monitored and the Tories called for an inquiry.
The BBC heard evidence of detainees being physically and racially abused while officers made sure violence was not captured on CCTV.
A GSL employee at Oakington, Jason Martin, was filmed while racially abusing an immigrant who refused to get out of bed.
"You think you're not going to do anything 'cos a white person tells you what to do. Well I'm afraid you're wrong.
"My great-grandfather shot your great-grandfather and nicked his f****** country off you for 200 years."
He then tips him out of bed.
Individuals were also filmed boasting of the abuse and about sexual relations with detainees.
The BBC's Simon Boazman said most of the officers he met at Oakington did try their best to treat the detainees with dignity and respect. But there were a significant minority who were racist.
Another BBC researcher, Andy Pagnacco, worked for GSL at Heathrow on a contract to transport asylum seekers.
He filmed colleagues advising how to act if a detainee turned violent. "As long as you can't see any cameras, hit 'em," one said.
GSL is currently facing a civil action from a Nigerian immigrant who claims he was assaulted by officers attempting to put him on a plane. He says he was so badly injured that officers had to return him to detention.
GSL said it did not tolerate racism or abuse and was launching an internal inquiry. It would be reviewing its staff systems as well as investigating the instances highlighted by the programme.
It said the majority of staff were "ordinary decent people doing a difficult job and they are feeling badly let down by a minority."
Mr Martin's new employers UK Detention Services said on Wednesday his job as a trainee prison officer had been terminated in light of the programme.
Immigration Minister Des Browne said he would consider what action to take once he was in possession of all the facts.
"There is absolutely no place for racism anywhere in our society, and particularly within the immigration system," he said.
"Detention and removal is an essential part of effective immigration controls, but it is vital that it is done with humanity and dignity, and I am committed to ensuring this is the case."
The documentary comes just months after an HM Prison Inspectorate report based on a visit to Oakington in June praised the "very good staff-detainee relations" and "caring and professional approach of most staff".
Anne Owers, HM Chief Inspector of Prisons, said 90% of detainees had told her team that staff treated them with respect but she added concern had been expressed about aspects of the centre and an inspection would be taking place.
Liberal Democrat home affairs spokesman Mark Oaten said the Home Office investigation needed a wider focus.
He said: "I think critically, we need to understand what is being done to effectively monitor these contracts when they're being awarded."
Shadow home secretary David Davis said: "The allegations of events at Oakington are disgraceful.
"If individuals are found guilty they should face disciplinary action."
Detention Undercover - The Real Story: BBC ONE, Wednesday 2 March, 2005 at 2100 GMT.