Shiv Sena chief Bal Thackeray was admitted to Lilavati Hospital in Bandra on Thursday afternoon after he complained of fever.
Party workers who visited Thackeray in Room No. 609 said he was suffering from suspected pneumonia and would remain in hospital for two days.
Hospital sources said necessary tests are being conducted on the 82-year-old leader.
His son and Sena executive president Uddhav Thackeray, who was at a party meeting at Rang Sharada where top leaders were discussing the election strategy and its alliance partner, rushed to the hospital. Among the early visitors were daughter-in-law Smita and MNS chief Raj Thackeray’s mother Kunda.
Senior party leader Manohar Joshi told the media that the decision on an alliance partner would be taken in a week’s time and that “all options were open.”