MILITARY police and Government officials have swooped on Essex's biggest redevelopment project and arrested a dozen labourers suspected of being illegal immigrants.

MILITARY police and Government officials have swooped on Essex's biggest redevelopment project and arrested a dozen labourers suspected of being illegal immigrants.

Work on the new £2 billion Colchester Garrison development got underway in May last year and should be finished by the end of 2009.

But yesterday it emerged that the redevelopment project was at the centre of an intelligence-led sting operation in which 12 workers were arrested.

An MoD Police spokesman said: “We can confirm we assisted with an Immigration Service operation at a construction site for new barracks in Berechurch Road, Colchester.”

The spokesman added that security at the barracks had not been compromised.

“This is a construction site next to the barracks, not a part of the active military barracks. There was no threat to security at the barracks,” he said.

It is understood the workers were detained by immigration officials whilst working as labourers on the redevelopment project next to the military barracks last Thursday, but details of the operation only came to light yesterday.

A spokeswoman for the Home Office confirmed that 12 arrests were made during the operation, which was conducted by the Immigration Service on an intelligence-led basis.

It is thought the swoop at the Garrison came in the wake of a tip off from a member of the public.

She said: “It resulted in the detention of 12 individuals, all suspected of breaching immigration conditions. One of those, a female from the Ukraine, has already been removed. The remaining 11 men are still under investigation.”

She added the arrested men were from Romania, Kosovo, Sri Lanka, Ghana and Nepal.

The Garrison redevelopment - one of the largest private finance projects in the country - is being overseen by RMPA Services, a consortium made up of Sir Robert McAlpine, Sodexho and Atkins.

The consortium was named as the preferred bidder for the contract in November 1999 following an extensive competition between rival firms.

The contract between the MoD and RMPA Services was made last year following more than a year's worth of legal negotiations and in-depth scrutiny.

Several new barracks are being built under the scheme, which will also see the creation of new working and living accommodation for 3,500 military and 220 civilian staff, training facilities, indoor and outdoor recreation facilities, a regional courts martial centre and new education and welfare facilities.

The redevelopment of the Garrison, some of which dates back to the Crimean War in the 19th Century, also includes new en-suite living spaces for single soldiers and major refurbishment to those parts of the Garrison which will be kept.