Kolkata, Dec 23 : Acclaimed classical singer Rashid Khan was hospitalised at a private hospital in south Kolkata on Saturday as his medical conditions turned critical. He is currently 55. Sources aware of the development said that the acclaimed singer of the Rampur-Sahaswan Gharana, had been suffering from prostate cancer for quite some time and he has even undergone treatment at Tata Memorial Cancer Hospital. However, at a later stage, he preferred to continue with his treatment in Kolkata only. As per the latest information available, his condition is critical, though there had not been any further deterioration in his medical conditions. Sources from his close associates said that despite his ailment, there was hardly any change in Khan's routine especially with regard to his daily practice of classical music. His routine starts at 4 a.m. His musical career started when he was just 11 years old. He hailed from the Rampur-Sahaswan Gharana, which has its origin in Mehboob Khan and his son Inyat Hussain Khan. Though mainly acclaimed as a classical singer, Rashid Khan's fusion and film number also received accolades. /IANS