Organisers of handover activities are being reminded to take precautions against fires, specially where crowds will gather. The Fire Services Department has distributed more than 5,000 leaflets on fire safety precautions since April as part of its handover contingency plan. 'We foresee many places and buildings will have a heavy flow of people heading for celebrations,' assistant divisional officer Cheng Chun-wai said. 'We want to keep the possibility of fire to a minimum,' he added. Queues stretched around MTR stations yesterday as people snapped-up handover-souvenir tickets. One million have been put on sale, each costing $25, and offering unlimited rides from midnight on June 30 until services end on July 1. Each buyer can purchase a maximum of four. Meanwhile, postage stamps and franks bearing the Queen, the Crown or the royal cypher will not be valid after June 30, the Post Office said in a reminder yesterday. The stamps can be exchanged for new ones at various post offices from July 3-31.