BEIJING, Feb. 2 -- Three more human cases of H7N9 bird flu, including one death, were reported in China on Sunday, according to local health authorities.

The cases included two in southern China's Guangdong Province and one in southern Guangxi Zhuang Autonomous Region.

A 63-year-old man died of the disease on Saturday in Shenzhen of Guangdong. Another confirmed case is a 37-year-old man from the city of Zhongshan, who is in critical condition, said the provincial health department.

Guangxi reported its first case this year on Sunday. The patient is a 75-year-old man from the city of Liuzhou. He is in critical condition,

The man had been in contact with live poultry before he fell sick on Jan. 27, the regional health department said in a statement.

Medical workers have disinfected his home and neighborhood, while 16 people who had close contact with him are under observation.

Local health authorities are investigating the source of the infection. They will not rule out the possibility of suspending live poultry trading.

It is the second case in Guangxi since 2009.

China has reported more than 100 human H7N9 cases, including over 20 deaths so far this year, with Zhejiang and Guangdong most affected.

Health authorities have strengthened H7N9 prevention and control measures including the closure of live poultry markets in some affected cities.