His condition was stated to be stable.
The 49-year-old minister was brought to Delhi from Lucknow and was admitted to the hospital on Friday after he suffered a seizure and an internal bleeding in the brain.
"He underwent a surgery for the removal of a lesion in the brain today. (He) is stable, conscious and recovering in the ICU," an AIIMS statement said.
According to a source at AIIMS, in scientific terms, the minister underwent cavernoma surgery. Cavernoma is a cluster of abnormal blood vessels, usually found in the brain and spinal cord.
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