Malaysian doctors say former Prime Minister Mahathir Mohamad has had further surgery after a recent heart bypass caused an infection.
Doctors say Mr. Mahathir underwent surgery late Saturday to remove infected tissue from his chest. An aide to Mr. Mahathir said Sunday that the former prime minister is not conscious and is breathing with the support of a respirator.
Officials say the next few days are a crucial period in the care for Mr. Mahathir.
The 82-year-old underwent heart bypass surgery on September 4, after suffering two heart attacks during the past 10 months. The heart operation was his second since 1989.
Mr. Mahathir resigned in 2003 after 22 years in power. He handed power to Abdullah Ahmad Badawi, but has since become a fierce critic of his chosen successor.