Revenue department detected central excise and service tax evasion of over Rs 13,620 crore in the 11-month period till February of 2011-12 fiscal, the government said.

Besides, during the investigation, central excise duty and service tax amounting to Rs 972.69 crore and Rs 1,182.64 crore, respectively, was realised, the Finance Ministry said in a statement.

The Central Board of Customs and Excise ( CBEC), responsible for collection of indirect taxes, detected a total central excise evasion of Rs 3,333.28 crore and service tax evasion amounting to Rs 10,286.73 crore April-February of 2011-12, it said.

Of these, the Directorate General of Central Excise Intelligence (DGCEI) officers detected evasion of central excise duties and service tax amounting to Rs 973.59 crore and Rs 4644.75 crore respectively.

"During the (DGCEI) investigation, the central excise and service tax dues amounting to Rs 219.49 crore and Rs 380.62 crore respectively, have also been recovered," the statement added.

The ministry statement further said that acting on a specific intelligence (on 28th / 29th March), the DGCEI "detected a case of service tax evasion by 'Skylark' Group of Companies, which is engaged in providing services of security agency and man power supply service all over India".

The estimated service tax evasion by these companies is about Rs 10 crore, the ministry added. It further said during the search conducted at various premises of the companies, "voluminous incriminating documents" indicating evasion of service tax as well as Indian currency (unaccounted) of Rs 77.5 lakhs were recovered.

"The mastermind behind the evasion is one Captain T C Yadav (Retd.), who used to float a number of companies engaged in providing security service and man power supply service under multiple identities," the Finance Ministry said.

Although the Group had been collecting service tax from its customers, it paid a small amount to the Government towards discharge of its service tax liability, while "illegally retaining with itself a significant amount collected as Service Tax from its customers," the release said.

It further said that Skylark Group is also running an education institute, Skylark School of Business and Technology (SSBT), and the service tax liability of these companies under the taxable service category of 'Commercial Coaching & Training Service' is under examination.

"Further investigations in this case are under progress," it added.