Prince Takamado died Thursday night at a Tokyo hospital after collapsing during a squash lesson at the Canadian Embassy in the afternoon, the Imperial Household Agency said. He was 47.

The prince collapsed after suffering ventricular fibrillation and went into a state of cardiopulmonary arrest, the agency said. He passed away at 10:52 p.m., it added.

Prince Takamado had been put on a heart-lung machine, and his wife, Princess Hisako, and mother, Princess Yuriko, wife of Prince Mikasa, were at his bedside.