Violence by inmates has also declined, the figures show.

The 1994 measure specified that the work by inmates reduce the cost of prisons to the state government.

According to one source, he has been given a new name to protect him from possible retaliation by other inmates.

She said she knew of no escapes by such inmates in the last five years.

A 42-year-old guard who had been taken hostage was shot dead by inmates on Sunday when he tried to escape.

He said the investigation unit would also look into misconduct by inmates.

Killings by inmates have fallen sharply in the last five years.

But advocates say accounts by current and former inmates suggest otherwise.

In the beginning, he used the program to stop much of the violence by inmates.

But accounts by former inmates of the Soviet labor camp system suggested that he was alive well into the 1970's.