Kalam collapsed during a speech at the IIM Shillong and was immediately rushed to the nearby Bethany Hospital where doctors put him on oxygen and are trying to revive him, a top police source told the Hindustan Times.

"He is in a critical condition. We are trying to revive him," John Sailo Ryntathiang, director of Bethany Hospital, told IANS.

"He is in the intensive care unit. We are examining him. We suspect that it could be cardiac arrest," Sailo said.

An IIM-S spokesperson said Kalam, who was President from 2002-2007, was in Shillong to attend a course on Liveable Planet Earth

Meghalaya Governor V Shanmughanathan and chief secretary P B O Warjri visited the hospital where Kalam has been admitted.