A magnitude 6 earthquake jolted Taiwan at 5: 32 p.m. Thursday for as much as 40 seconds, but caused no major damage around the country, the National Police Agency (NPA) reported later that day. As of 8 p.m., only one injury had been reported -- a girl at a senior high school in central Taiwan's Taichung County who was slightly injured after being hit on the head by falling piece of ceiling. The temblor, which had its epicenter at Mingchien village in central Taiwan's Nantou County, was felt around the country, from Taipei City in the north to Kaohsiung City in the south, although Nantou and Yunlin counties recorded the highest intensities. It was the worst quake to rock Taiwan since the devastating 7.3 magnitude earthquake of Sept. 21, 1999, the Central Weather Bureau (CWB) said. According to a CWB official, the quake was related seismically to the 921 temblor, but the amount of energy it released was only 1/100 of that produced by the 921 earthquake, which released energy 'equivalent to that of 50 atomic bombs.' The latest quake was a natural release of energy after the 921 incident, she explained. Hundreds of households in Nantou and Changhua counties suffered electricity outages, and one house in a Changhua township suffered minor damage when a wall collapsed, according to the National Fire Agency. Cellphone services were lost in Mingchien village, but land lines were unaffected. Meanwhile, road and rail traffic remained largely unaffected. Taiwan Railway Administration networks continued normally, although High Speed Railway services in parts of central areas were halted briefly and the Kaohsiung Mass Rapid Transit system was stopped for a two-minute period. In northern Taiwan, no damage was reported from high-tech companies based at the Hsinchu Science Park. 