"He was being given sleeping pills along with other medicines regularly since he became the Chief Minister of Uttarakhand (2002-07)," Bhawanidutt Bhatt, an OSD of Tiwari, said here today.
"As part of a conspiracy, Tiwari was given sleeping pills four times a day along with his other medicines. This had affected his health...," Bhatt said.
Asked about the persons involved in the alleged conspiracy, he said they were among his close ones and private staff. Bhatt claimed Tiwari's close ones used to take undue advantage of his drowsiness and made him sign important papers.
"Tiwari was being given sleeping pills also when he was Governor of Andhra Pradesh. Later, he had to resign following an alleged sex scandal case," he claimed.
"We came to know about the foul play eight months ago when his health was continuously deteriorating following which his nephew Manish Tiwari started taking care of him," he said.
When contacted, 88-year-old Tiwari refused to comment on the issue.
However, his rivals in the Congress party termed it a "political stunt" and said Tiwari is trying to gain mileage after he was embroiled in controversies.