More than 800,000 people across Japan have taken part in an annual drill to prepare for a major earthquake.
Hundreds of thousands of people took part in the drill
Police, firefighters and volunteers practised their response to a magnitude 7.3 quake directly under Tokyo.
These drills are held every year on the anniversary of the Great Kanto earthquake, which killed more than 140,000 people in 1923.
This year's exercise included personnel from the US and South Korea for the first time.
In a mock news conference on Friday morning, Prime Minister Junichiro Koizumi said that massive damage had been caused by an earthquake, and urged people not to panic.
Then emergency procedures got underway, with helicopters picking up "evacuees" and firefighters helping people from buildings.
Japan is in an area prone to regular and in some cases serious earthquakes.
Tokyo, which has a population of 12 million, sits on three major seismic fault-lines.
A large-scale earthquake is thought to be several years overdue, and despite all their efforts to prepare the public and reinforce buildings, officials still predict that a large tremor could kill more than 10,000 of the city's inhabitants.