The 72-year-old is currently in the intensive care unit (ICU), the source said. 

Yechury was admitted to the AIIMS on August 19 for treatment of a pneumonia-like chest infection. 

The exact nature of his ailment was not revealed by the hospital. In a statement issued on Saturday, the CPI-M had said he is under the care of a team of specialist doctors who are treating him for respiratory infection. 

Yechury had recently also undergone cataract surgery. -- PTI