Three more people were confirmed to be infected with the H7N9 bird flu in three Chinese provinces, health authorities said Sunday.

The infection of a man, 83, from Huai'an in East China's Jiangsu Province was confirmed Sunday morning, according to the provincial health and family planning commission.

The man, surnamed Han, brought eight chickens he had raised to a market for slaughtering. He is in critical condition, according to the commission.

So far, 13 human H7N9 cases have been reported in Jiangsu Province this year, including four deaths, according to the commission.

Meanwhile, a 44-year-old man surnamed Qin was confirmed to be infected with the virus Saturday. The patient is in critical condition and is receiving treatment at a hospital in Shenzhen, Guangdong Province, where he lives, according to a statement issued by the provincial health and family planning commission.

The other case was reported in Hunan Province, where a 46-year-old man tested positive for the H7N9 bird flu virus in the city of Loudi. The man, surnamed Yan, is the 10th case reported in Hunan. He is now receiving treatment at a local hospital, according to the provincial health department.