By Andrew Bomford
Social affairs correspondent, BBC News
A swoop on illegal workers at a chicken processing plant
There has been a dramatic increase in the number of employers being prosecuted for hiring illegal immigrants, the BBC has learned.
In the two months since the end of February, when there was a change in the law, 137 businesses were caught employing illegal immigrants.
This is 10 times the number caught in 2007, and more than double the number prosecuted in the previous decade.
Employers face fines of up to £10,000 for each illegal immigrant they employ.
In the last two months fines of about £500,000 have been handed out. Persistent offenders also face a jail sentence.
"There are dodgy employers out there who are trying to undercut their competitors and drive down British wages by employing people illegally, so we've come up with this new way of taking much faster on-the-spot action," Immigration Minister Liam Byrne told the BBC.
It's quite clear that this new regime, which is part of a big shake-up of Britain's border security, is already beginning to work
Liam Byrne Immigration Minister
"It's quite clear that this new regime, which is part of a big shake-up of Britain's border security, is already beginning to work."
To see the policy in action the BBC was invited out on an enforcement operation with officers from the UK Border Agency.
About 60 officers, backed up by the police, walked into a chicken processing factory in Derbyshire. Police intelligence had suggested that illegal immigrants were working there.
In a large processing room 56 workers, all of them from overseas, were preparing chicken pieces for the retail trade.
Uk BA officers burst into the room, shouting loudly and telling the workers to put their knives down.
The shocked workers were lined up against a wall and told they would be questioned to see if they were in the country legally.
Immigration Minister Liam Byrne praised the successes
After several hours of questioning it was determined that 22 of the workers were illegal immigrants. Fingerprints were taken and paperwork examined.
The illegal immigrants, from a variety of countries including Afghanistan, Pakistan and India, were led out of the building in handcuffs and taken to police stations.
The rest of the workers were sent home.
Investigations into the owners of the company are ongoing and so far no fines have been levied.
Employers are given an opportunity to respond or explain why illegal immigrants were working for them. If no satisfactory excuse is forthcoming sizeable fines can follow.
It is not always easy for employers to tell whether someone is in the country legally.
The BBC spoke to one man, a restaurant owner in the home counties, who was recently fined £6,000 after four illegal immigrants were found working in his kitchen during a raid.
Faisal Ahmed told us that two of the men had only started working the day before and had provided P45 payment documents from their previous employer and had National Insurance numbers.
He said he assumed they were here legally.
The UK BA now provides a phone number which employers can use to check the status of potential employees.
"If anyone comes here with a British passport how do I know if this is a fake passport?" he asked.
"I haven't got any kind of machine to check it. Now the court has given me some documents showing me how to check if I think there's anything dodgy."
Since February there has been a 40% increase in the numbers of UK BA enforcement operations.
Indian restaurant owners have started complaining that they are being targeted in the crackdown.
Raids often take place in the evening when restaurants are busy with customers.
They have to be closed down while the operations are under way and diners are sent home.
We've got to sustain this over time and employers have got to realise that this is not a short cut to cutting costs
Chris Huhne Liberal Democrat
Restaurant owners say it is giving them a bad reputation at a time when they are finding it hard to recruit chefs from overseas because of much tighter immigration restrictions.
The government is facing a major problem in dealing with the illegal immigrants rounded up in enforcement operations.
Only two of the 22 arrested on the raid on the chicken processing plant were deported immediately.
It can take months to locate the necessary paperwork for deportations and some cannot be deported at all if they come from countries where it is unsafe to return them.
Employers claim it is hard to spot faked passports
According to the National Audit Office, it costs £11,000 per person to deport them.
With an estimated total of more than 500,000 illegal immigrants in Britain, the government is facing a bill of more than £5bn to deport them all - if they can catch them.
Last year 63,140 people were removed from the country.
The Conservatives said the government was "painfully slow" in dealing with the issue.
Shadow immigration minister Damian Green said: "Ten times a minuscule number is still a small number."
The Liberal Democrats welcomed the government's new crackdown on employers, but said it was long overdue.
"If we are going to be effective in reducing the pull factor of employers employing illegal immigrants then it's not good enough just to have a little blitz with a few prosecutions in one year," said Chris Huhne, the party's home affairs spokesman.
"We've got to sustain this over time and employers have got to realise that this is not a short cut to cutting costs."
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