"The Cabinet Secretary, whose extension period was slated to end on March 31, has taken pre-mature retirement with effect from March 9," they said.
Singh, who had retired in May, 2010, was given two years extension by the state government which was due to expire on March 31.
"As his services continued even after superannuation, it is called as pre-mature retirement," the sources added.
Singh, who rose to the rank of the cabinet secretary of the state despite being a non-IAS officer, was considered close to outgoing Chief Minister Mayawati.
His tenure as cabinet secretary was marred by controversies. Singh's appointment as cabinet secretary had been challenged in the court several times.
Image: Shashank Shekhar Singh
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