At least nine people were killed when a magnitude-6.5 earthquake struck southern Japan on Thursday, destroying homes and businesses with aftershocks following. As sunlight begins to break Friday and officials begin to assess the damage, a Japanese government spokesman said at least 761 people had been injured, at least 44 critically, with people likely caught in collapsed buildings.

Approximately 1,600 soldiers have been sent to the area to deliver supplies as approximately 16,000 homes remain without power and 38,000 remain without gas, the BBC reported. The U.S. Geological Survey upgraded its damage assessment to the red level, signifying extensive damage. Early estimates predicted damage costs could range from $1 billion to $10 billion.

“Because of the night darkness, the extent of damage is still unclear,” said spokesman Yoshihide Suga. He said he would visit the region Friday to assess the extent of the damage. Prime Minister Shinzo Abe promised to carry out whatever relief operations were possible during the night.

Local residents described the sudden shaking and destruction in their homes and neighborhoods. Experts warned that aftershocks could continue for several days.

“There was a ka-boom and the whole house shook violently sideways,” said Takahiko Morita, a resident of Mashiki who spoke with a Japanese broadcaster. “Furniture and bookshelves fell down, and books were all over the floor.”

The worst damage was sustained in the town of Mashiki on Japan’s southernmost main island Kyushu, the Associated Press reported. There was no tsunami risk associated with the earthquake and officials said the nearest nuclear facilities were 74 miles from the epicenter and not in any danger.

Widespread damage from the catastrophic magnitude-9.0 earthquake and tsunami that struck northeastern Japan in 2011 and wrecked the Fukushima nuclear plant cost the government more than $300 billion for a total of 6 percent of the country’s 2010 economic output, the BBC reported.