Tokyo, Jul 7 (IANS): The death toll due to the torrential rain in Japan's Kyushu region increased to 52 on Tuesday, with the government issuing its highest alert as the Chikugo river in Oita prefecture overflowed.

Kumamoto prefecture registered the highest number of victims at 51, while 11 people were reported missing, The Japan Times quoted authorities as saying.

The 52nd victim, a woman in Omuta Fukuoka prefecture, was found at her submerged home on Monday night and was confirmed dead Tuesday at a hospital.

In Omuta, about 200 people were left stranded at two evacuation centres after floodwaters surged in the area.

The Chikugo River, the largest in the Kyushu region, overflowed in Hita, Oita prefecture, prompting a local meteorological observatory and the land ministry to issue the highest-level alert to residents on Tuesday morning.

The death toll from the heavy rains that started in the early hours of July 4 is expected to climb as search efforts for the missing continued at sites hit by landslides and floods.