High alert

Summer is the busiest time for the police in Qinhuangdao.

"We are not allowed to take leave or vacations during this time. That includes some police officers from Beijing and other cities in Hebei province," said a policeman in his early 30s who declined to be named.

The security deployment includes numerous plainclothes police, sporting well-pressed attire and sunglasses, who sit on benches and keep a lookout on passers-by, he said.