Senior politician and former governor N D Tiwari was at Max Hospital in Saket after suffering a brain stroke, his son Rohit Shekhar Tiwari said.
Sources at Max Hospital in Saket said the condition of 91-year-old Tiwari, a former chief minister of Uttar Pradesh and Uttarakhand, is serious and he is being kept under observation in the Intensive Care Unit (ICU).
A team of doctors is attending to him, they said.
Rohit said his father fell unconscious this morning while having tea at his house here.
-With PTI inputs.