British authorities have rounded up scores of "immigrant offenders" in a nationwide operation condemned as racist, launched days after the government began telling illegal migrants to “go home or face arrest”.

The Home Office, which has responsibility for immigration, was widely criticised on Wednesday for the spot-checks at stations and on streets in areas including London, Durham, Manchester, Wales and Somerset leading to the arrest of 139 people. 

The home office's official Twitter account trumpeted the success, created a new hashtag #immigrantoffenders, and published pictures of the spot-checks.

But Twitter was filled with protests and comments condemning the operations, which many witnesses said specifically targeted ethnic minorities and non-white people.

The UK government's 'go home' campaign.

Witnesses who saw spot-checks in London claimed that immigration officers stopped only non-whites, and became aggressive when challenged.

Phil O’Shea told the Kilburn Times: “They appeared to be stopping and questioning every non-white person, many of whom were clearly ordinary Kensal Green residents going to work. When I queried what was going on, I was threatened with arrest for obstruction and was told to ‘crack on’.”

The spot-checks come days after a widely derided poster campaign telling illegal immigrants to "go home of face arrest".

The poster boards have been driven around cities in an effort, the government says, to encourage those in the UK illegally to come clean.

The opposition Labour MP Barry Gardiner has written to the home secretary, Theresa May, demanding an investigation into a campaign which he said violated “fundamental freedoms”, the Independent newspaper reported. 

“We do not yet live in a society where the police or any other officers of the law are entitled to detain people without reasonable justification and demand their papers,” Mr Gardiner wrote. “The actions of your department would however appear to be hastening us in that direction.”

Heavy penalties

The Home Office said the spot checks were designed to send a message to employers who exploited "illegal labour and to people who are in the UK illegally".

It gave the nationalities of some of those arrested: A Ukrainian woman, an Indian man aged and a Brazilian woman were arrested at Kensal Green in North-West London.

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It said those arrested were being questioned, and those who have no right to be in the country would be removed. Employers would face a fines the equivalent of up to $15,000.

Immigration Minister Mark Harper said: "We are sending a clear message to employers who choose to use illegal labour. We will find you and you will pay a heavy penalty.

"Illegal working undercuts legitimate businesses and is often linked to exploitative behaviour such as tax evasion and harmful working conditions.

"We will not allow the growth of a shadow economy for illegal migrants."

Source: Al Jazeera