The government today curtailed tenure of Ajay Tyagi as next chief of capital market regulator SEBI by two years. This comes barely a week after his name was cleared to succeed incumbent U K Sinha with a five-year term.Tyagi will now join as the Securities and Exchange Boardof India (Sebi) Chairman for an initial period of three years. No reason has been given behind the curtailment of his term.Tyagi will take over as Sebi chief after the extended tenure of Sinha ends on March 1.The Appointments Committee of the Cabinet, headed byPrime Minister Narendra Modi, had on February 10 approvedTyagi's appointment for a period not exceeding five years ortill the age of 65 years, as per an order issued earlier bythe Personnel Ministry.SEBI, besides regulating stock exchanges, also supervisesvarious kinds of market entities including brokers, mutualfunds, FIIs, rating agencies and investment bankers, as alsothousands of listed companies.