GUANGZHOU - Two new confirmed human cases of the H7N9-strain of avian influenza were reported in South China's Guangdong province on Monday.

Both patients -- Yang, 42, and Zhu, 52 -- are in a critical condition, according to the provincial health and family planning commission.

Earlier this month, authorities in Guangdong and Hong Kong ordered the culling of thousands of chickens after birds exported from Guangdong to Hong Kong tested positive for the virus.

Hong Kong raised its hospital response level "serious" from "alert" after a 68-year-old woman, who had arrived from Shenzhen two weeks earlier, was hospitalized on Dec. 25 with H7N9.

This was the region's first case since early 2014.