Photo taken on July 23, 2015 shows the detained Chinese student Liu Tuo talking at a local police station in the city of Samarra, northen Iraq. The Chinese college student detained in northern Iraq was freed by local police on Monday, according to Chinese embassy in the country. Photo: Xinhua

Photo taken on July 23, 2015 shows the local police station where the detained Chinese student Liu Tuo stayed in the city of Samarra, northen Iraq. The Chinese college student detained in northern Iraq was freed by local police on Monday, according to Chinese embassy in the country. Photo: Xinhua

Photo taken on July 23, 2015 shows Chinese student Liu Tuo (in white) detained by Iraqi police in the city of Samarra, northen Iraq. The Chinese college student detained in northern Iraq was freed by local police on Monday, according to Chinese embassy in the country. Photo: Xinhua

Photo taken on July 23, 2015 shows the Great Mosque of Samarra, where the Chinese student Liu Tuo visited before being detained by Iraqi police in the city of Samarra, northen Iraq. The Chinese college student detained in northern Iraq was freed by local police on Monday, according to Chinese embassy in the country. Photo: Xinhua