SECURITY checks at Shanghai’s two airports are being upgraded from today and all passengers and baggage will be tested for explosive materials from next week.

Airport authorities gave no reason for the security upgrade. However, the city is hosting an important Asian summit on May 20 and 21 which will be chaired by President Xi Jinping.

Delegations from nearly 40 countries and international organizations will be arriving in the city for the Shanghai Summit of the Conference on Interaction and Confidence Building Measures in Asia.