Samajwadi Party founder Mulayam Singh Yadav died on Monday in Medanta hospital in Gurugram, where he was undergoing treatment.
"Mere adarniya pitaji aur sabke netaji nahi rahe - Akhilesh Yadav," the SP tweeted from its Twitter handle.
Mulayam, 82, was admitted in the hospital since August and was shifted in ICU on October 2 and had been on lifesaving drugs since.
(With PTI Inputs)