An inmate at Matsue Prison in Matsue, Shimane Prefecture, has filed a ¥1 million damages suit against the government and the prison, claiming he suffered mental distress due to the unsanitary condition of his cell.

In the complaint filed with the Matsue District Court, the inmate claims the prison dried his bedding in the sun only three times during a 21-month period through last June, causing him to suffer from ticks and lice.

Two other inmates were relocated to other cells because they were infected with skin diseases caused by the ticks, according to the complaint.

While it depends on each prison how frequently cells are cleaned or bedding is aired, Matsue Prison said it conducts mattress airing systematically in accordance with weather conditions.

"We air the mattresses according to schedule, but we sometimes cannot do so because there is much rain in the Sanin region," said an official at a correctional office in Hiroshima Prefecture, which has jurisdiction over Matsue Prison.