Emergency and disaster preparedness experts yesterday praised countries hit by December's tsunami for their speedy reaction to the earthquake. But the observers warned of the urgency of a tsunami detection system, lack of which was blamed for the high death toll three months ago. The deputy executive director of the Bangkok-based Asian Disaster Preparedness Centre, Earl Kessler, said governments this time had done 'a good job'. 'People are now aware of what they're trying to do and know what they're looking for,' Mr Kessler said. 'Lessons have been learned and hopefully simulations can be built into everyday work so that these won't be forgotten.' The United Nations Development Programme's regional adviser on disaster reduction, Michael Ernst, said governments transmitted warnings of a possible tsunami to television and radio stations soon after learning of the quake. 'What wasn't present, and will take some time, are the wave measuring devices planned for the Indian Ocean,' Mr Ernst said from Bangkok. An aid agency worker in Indonesian's Aceh province said word of the quake spread rapidly. Within minutes, people had fled their homes. 'People could be seen driving to the mountains, but began drifting back after an hour or so when the danger had passed,' said the worker, who declined to be identified.