India's top court has ordered a federal investigation into a multimillion-dollar college admission and government job recruitment scandal in central India said to be linked to dozens of mysterious deaths.

The Supreme Court on Thursday ordered the Central Bureau of Investigation to investigate the alleged irregularities in job recruitment and college admissions as well as the deaths of nearly 50 people associated with the scam.

Police have arrested hundreds of officials for allegedly rigging eligibility tests for admission to medical colleges and recruitment for jobs in the police force, schools and banking sector.

Opposition Congress party leaders had been demanding a federal inquiry into the scandal as dozens of people, either witnesses or accused participants in the scam, have died over the last five years in inexplicable circumstances.