The legendary Ghazal singer, who is affectionately called as Khan Sahib, has been admitted to a private hospital following a lung infection, according to the report.
Earlier, Hassan's son Arif Mehdi had requested the government of Sindh province to bear the expenses for his father's treatment.
Hassan, who is a former playback singer for Pakistani movies, has also been bestowed with the title 'Shahenshah-e-Ghazal'.