Veteran Bengali actor Soumitra Chatterjee was put on non-invasive ventilation as his physical condition deteriorated on Monday night.
The 85-year old actor was unconscious at the time with fever and breathing complications.
Physicians said, they would run electrocardiogram and echocardiogram tests on the actor.
Pradeep Tandon, chief executive officer (CEO) of Bellevue Nursing Home, said on Monday that they were more concerned about Soumitra Chatterjee's other ailments. They are hopeful that the veteran star will recover soon.
IANS reports, Chatterjee, who had tested coronavirus positive on 5 October, was suffering from several comorbidities. He was immediately shifted to an ICU for close monitoring.
A day after his COVID-19 test on 5 October gave positive report, he was admitted to the hospital but in a stable condition.
He had attended the shoot floor at Bharatlaxmi Studio on 1 October. The next shooting schedule was on 7 October.
It was learnt that the actor had chronic obstructive pulmonary disease-related problems. Last year, he had suffered a bout of pneumonia and was admitted to a hospital for a few days.
The actor has been suffering from prostate cancer, diabetes and high blood pressure among other sicknesses.