* Charges include conspiracy, forgery, cheating
* Multi-billion dollar graft case potentially biggest ever
* Court orders accused to appear April 13
(Adds denial from company)
By C.J. Kuncheria
NEW DELHI, April 2 (Reuters) - Indian police charged three telecoms firms, a former minister and several executives with a range of crimes on Saturday in a multi-billion dollar licensing scandal, potentially the biggest graft case in Indian history.
Charges in the case, which has rocked India's business and government establishments, were handed down against former telecoms minister Andimuthu Raja and the firms Reliance Telecom, Unitech Wireless and Swan.
Reliance Telecom is a unit of no. 2 mobile phone operator Reliance Communications, part of Reliance ADA group, one of India's biggest and most influential conglomerates.
Unitech Wireless, owned by realty firm Unitech, is the Indian joint venture partner of Norway's Telenor and Swan is the joint venture partner of Emirates operator Etisalat.
Raja was the telecoms minister at the time of a flawed 2008 mobile phone license allocation process.
"The charges are conspiracy, cheating, forgery of documents, abuse of official position and abetment," A.K. Singh, special public prosecutor told reporters after the charges were filed.
The managing director of Unitech, the vice chairman of Etisalat's India arm, three officials from Reliance and two other government officials were also charged.
Not all of the accused face all five charges.
The graft scandal has damaged confidence in the Congress-led coalition government, led to calls for the resignation of Prime Minister Manmohan Singh, and worried investors in Asia's third-largest economy.
It is one of the several corruption scandals that have emerged during Singh's second term, hobbling policymaking and diverting the government's attention away from pushing forward crucial economic reforms.
Some of India's leading businesses have been questioned and past official decisions scrutinised or reversed. These events have weighed on stocks, with the Mumbai market ending the March quarter as the world's worst performer.
India may have lost as much as $39 billion due to violations of rules when lucrative mobile phone licences and radio spectrum were granted in 2008, the state auditor estimated, a sum equivalent to the country's defence budget.
Raja was forced to resign and later arrested over the auditor's report. He has been accused in court earlier of taking bribes from two firms which are now part of the India operations of Etisalat and of Telenor.
Those charged include: Shahid Balwa, vice chairman of Etisalat's Indian arm; Gautam Doshi, a group managing director of Reliance ADA; Reliance senior vice presidents Hari Nair and Surendra Pipara; and Sanjay Chandra, Unitech managing director. All of the accused were ordered to appear in court on April 13.
A statement from Reliance Telecom said the firm and its officials denied all charges.
Police have earlier questioned Anil Ambani, the billionaire chairman of Reliance ADA group, and Prashant Ruia, chief executive of steel-to-telecoms conglomerate Essar group. A parliamentary panel probing the scandal has summoned Ambani and iconic business tycoon Ratan Tata for questioning next week.
All of the accused have denied any wrongdoing.
The telecoms ministry is considering whether to cancel several licences, after the auditor's report accused firms of not being eligible for them, sparking off worries about regulatory stability.
The Supreme Court, under a tough new chief justice, has been monitoring the progress of the case after having reprimanded Singh for not moving quick enough to act against his minister.
Faced with a resurgent opposition, Singh's government has not been able to undertake economic reforms such as freeing up diesel prices and allowing foreign investors into the supermarket sector.
Corruption scandals, which include charges of graft at the 2010 Commonwealth Games and of bribe-taking by officials at state-run banks, have tarnished Singh's image as a clean and effective leader.
They could also affect the performance of the ruling Congress party in five state elections that begin in mid-April. (Reporting by CJ Kuncheria; Editing by Peter Graff)