Nearly 250,000 people have been told to leave their homes amid fears of further quakes in Japan, an aid agency says.

Naoki Kokawa, advisor to the Japanese Red Cross Society, told the BBC that more medical teams were being dispatched to evacuation centres.

Two powerful earthquakes hit the south-western island of Kyushu last week killing at least 42 people.

Japan's meteorological agency has also warned that more tremors are likely to hit in the coming days.

More than 1,000 people are injured and there has been widespread damage to buildings, houses, roads and bridges.

About 30,000 rescue workers are looking for survivors. Police said 11 people are still missing, public broadcaster NHK reported.

"There are still missing people. We want to make further efforts to rescue and save people and prioritise human lives," Prime Minister Shinzo Abe said in parliament on Monday. He also said he wanted to declare the region a disaster zone.

A 61-year-old woman was found dead near her collapsed house in Kumamoto prefecture on Sunday, Japan Times reported.

Saturday's magnitude-7.3 quake struck at 01:25 (15:25 GMT on Friday) close to the city of Kumamoto, which had been hit by a magnitude-6.4 quake on Thursday night.

Both quakes were shallow, causing huge damage to roads, bridges and tunnels. Big landslides cut off remote mountain villages.

The US military said it was ready to provide aerial support for the relief efforts.