NANJING -?Four people in East China's Jiangsu province have been confirmed as being infected with the lesser-known H7N9 bird flu, bringing the total number of infections in the country to seven.

The four, from four cities in Jiangsu, are in critical conditions and are under emergency treatment, the Jiangsu provincial health bureau said Tuesday in a statement.

China Sunday reported three H7N9 bird flu cases, two in Shanghai and one in Anhui, the first human infections of the bird flu strain. The two in Shanghai have died and the one from Anhui was in critical condition and was under treatment in Nanjing, capital of Jiangsu.

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