Japan's prisons are at their most crowded since records began, a report warned on Friday.
Japanese prisons have not been this full for years
A Justice Ministry survey said that some prisoners were forced to sleep in libraries, and some prison canteens could not accommodate their inmates.
Jails are said to be at 117% capacity, the highest since the Justice Ministry began keeping records in 1972.
The increase was due to rising violent crime and a trend towards longer sentences, a ministry official said.
A prison in Sapporo, on the northern-most island of Hokkaido, ranked as the most crowded, and is currently running at 122% of its capacity.
"We have to put two inmates in single-person cells, but it's complicated because we have to carefully choose the combinations so as not to put accomplices or members of the
same gangster groups together," said Norio Sonobe, a ministry official in charge of the
The Justice Ministry study said that if the number of new inmates kept rising at the current level, the prison population could exceed
66,000 by the end of 2007.
But despite the increase, Japan still has one of the lowest rates of incarceration among developed countries.
Recent UK government statistics show Japan has 48 inmates for every 100,000 people, compared with 139 in the UK and 686 in the United States.