LUSAKA, Oct. 29 (Xinhua) -- Zambian President Michael Sata has died in London, local private media outlets said on Wednesday.

Sata had died on Tuesday evening at London's King Edward VII hospital, the private Muzi television station, the Zambia Reports and Zambian Watchdog websites reported.

No official announcement or comment has been made yet.

The Zambian leader was evacuated for further specialized treatment abroad on Oct. 19, accompanied by First Lady Christine Kaseba-Sata and some family members.

Sata's health has been a subject of debate since June this year when he disappeared from the public for almost three months, with speculation that he had gone to Israel for specialized treatment while the government said he had gone on a working holiday.

Last month, fear gripped the southern African nation when some international media reported that he had collapsed while attending the UN General Assembly in the United States.

Sata became president after winning the 2011 elections.