TOKYO, Aug. 25 (Xinhua) -- The Japan Meteorological Agency issued a false alarm saying a strong earthquake was imminent in Tokyo and surrounding areas early Tuesday, casing subway and other train services to briefly halt shortly before morning rush hour, Kyodo News reported.
The quake warning was issued around 6:37 a.m., but no jolt perceptible to people was observed in the region, the agency said, blaming the error on a possible computer glitch.
The alert caused Tokyo Metro to suspend services on eight of its subway lines for two to nine minutes, including halting trains, but the timetables were restored by 8 a.m. Other railways were also affected.
A quake centered under the sea east of Chiba Prefecture occurred after the alarm, and the agency said its quake alert system may have misjudged signals of this tremor, Kyodo said.
The system is designed to release a warning when a strong quake of intensity at least lower 5 on the Japanese seismic scale of 7 is forecast based on minor initial tremors detected by seismometers