The death toll for a magnitude 7.1 earthquake that struck Kumamoto Prefecture on Tuesday has risen to 28, including those authorities are still working to determine whether they are quake-related, as rescuers race against the clock to find survivors before the crucial 72-hour mark.

At least five of the deaths were caused by an explosion that brought down a major shopping mall in the town of Kashima, while another five died at a Nippon Paper Industries¡¯ mill in the city of Yatsushiro, Chief Cabinet Secretary Minoru Kihara confirmed Thursday.?

¡°Rescue efforts are a race against time,¡± Kihara said, adding that the police, firefighters and Self-Defense Forces personnel will continue to work tirelessly to save lives and rescue those affected.?

The Kumamoto Prefectural Government on Thursday said six people are in critical condition and five others seriously injured. It still hasn¡¯t been able to determine the scale of damage to housing.

Cracks are seen on a road in the town of Hikawa, Kumamoto Prefecture, on Wednesday afternoon following a magnitude 7.1 earthquake that hit the region a day earlier.
Cracks are seen on a road in the town of Hikawa, Kumamoto Prefecture, on Wednesday afternoon following a magnitude 7.1 earthquake that hit the region a day earlier. | JIJI

About 10,000 people have evacuated from their homes and more than 400 shelters have been set up following the quake on Tuesday evening, which registered a maximum shindo 7 on the Japanese seismic intensity scale.?

With parts of the disaster-hit area being cut off of water and electricity, authorities are warning evacuees to be wary of heatstroke. As of Thursday morning, about 23,000 households remained without electricity, and 74,800 households without water.

Temperatures are forecast to exceed 35 degrees Celsius for the rest of the week.

Meanwhile, evacuees are forming long lines at water trucks. Authorities are urging people to drink water even before getting thirsty, wear caps or hats, and stay in the shade to avoid the sun.?

Evacuees rest at a shelter in the city of Uki, Kumamoto Prefecture, on Wednesday.
Evacuees rest at a shelter in the city of Uki, Kumamoto Prefecture, on Wednesday. | AFP-JIJI

Many others are taking refuge from the heat in their cars, where they have air conditioning, though this could heighten the risk of economy class syndrome, a medical condition in which blood clots form in the veins, usually in the legs, when people sit in the same position for hours. Flexing one¡¯s toes and walking from time to time as well as drinking water help cut the risk of the condition.

To reduce discomfort and health risks, Prime Minister Sanae Takaichi said Wednesday the government would ensure there is a sufficient supply of gasoline and that healthcare providers regularly check on evacuees.

A total of 3,300 portable air conditioners are expected to be sent to the affected region. As of Wednesday afternoon, around 300 had arrived in the town of Mashiki, according to local authorities.?

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