Bomb disposal officers cordoned off a shopping centre in Yuen Long after three robbers tied up an 18-year-old, stole his mobile phone and put a suspicious object in his backpack. The victim was pushed into the back stairwell of Yuen Long Plaza in Castle Peak Road at 2.45pm. The robbers told the victim his backpack would explode if he moved. The victim was found at 3pm. The plaza was cordoned off for a controlled explosion. The pack contained firecrackers.