CHANGSHA - Two people were detained after police found they were involved in smuggling 618 wild birds by bus, police in central China's Hunan province said on Saturday.

A villager surnamed Wu, in a township of Xiangtan City, Hunan, transported the wild birds in eight cases in a bus earlier this month to a dealer surnamed Zhong in Sanshui City, Guangdong Province, according to the Xiangtan City Forestry Public Security Bureau.

But informed police stopped the bus at a highway toll station in Hunan and captured all the boxes of birds -- 612 aquatic birds and six night herns.

Police arrested Wu in a club in Xiangtan on Wednesday and Zhong in Sanshui on Friday afternoon.

All the birds have been set free in two parks in Xiangtan, police said.

The two suspects face criminal charges.

The State Forestry Administration (SFA) said in an emergency notice on Monday that Hunan's forest authorities should quickly investigate bird slaughtering and strictly penalize those involved.

The SFA has also ordered local authorities across the country to start screening for illegal activity regarding migrant birds, intensify law enforcement and supervision and step up publicity efforts to ensure safe migration.

Hunan's forest authorities said they have launched a related campaign that will last from October 18 to November 20. The campaign will include a crackdown on the illegal killing of wild birds, as well as related transactions.