In this file photo taken on May 2, 2016, Chinese and Italian police officers check the documents of a Chinese tourist group outside the Colosseum in Rome, Italy. In 2014, China and Italy agreed to launch the joint patrol program during peak travel seasons. Since May 2016, China has sent three groups of police officers to patrol streets in Italy. Italian officers were first invited to the joint patrol in Beijing and Shanghai in April 2017. (Xinhua/Jin Yu)