Samajwadi Party founder Mulayam Singh Yadav's wife Sadhana Gupta passed away at a private hospital in Gurugram on Saturday after a prolonged illness.
She was suffering from lung infection and other ailments for the past three months. She was undergoing treatment at Medanta Hospital, where she breathed her last on Saturday morning, SP sources in Lucknow said.
Samajwadi Party in a tweet informed that Sadhana Gupta was the second wife of Mulayam Singh Yadav. His first wife and the mother of SP chief Akhilesh Yadav, Malti Devi, died in 2003.
In a tweet in Hindi, the Samajwadi Party paid a "heartfelt tribute" to Sadhana Gupta.
Mulayam Singh Yadav was in Delhi at the time of his wife's death, the party sources said, adding that the body was being brought to Lucknow.
Akhilesh Yadav is overseeing the arrangements and the details of the last rites will be finalised soon, they added.
Senior party leaders and workers started arriving at the SP patron's house soon after the news of Sadhana Gupta's death broke.
In a tweet, Uttar Pradesh Chief Minister Yogi Adityanath and Deputy Chief Minister Keshav Prasad Maurya extended their condolences to Mulayam Singh Yadav and his family.