Celebrated singer S P Balasubrahmanyam is on maximum life support after his condition deteriorated in the last 24 hours, Chennai's MGM Healthcare hospital said in a medical bulletin on Thursday. The singer's close friend, actor Kamal Haasan, visited the hospital on Thursday night. SPB, as the singer is fondly called, has been in hospital since August 5 after testing positive for COVID-19. The 74-year-old singer no longer has the coronavirus - he tested negative on September 8 - but he could not be taken off the ventilator because of the condition of his lungs, Mr Balasubrahmanyam's son S P Charan said earlier this month.