Two strong earthquakes hit between Japan's southernmost islands and the coast of Taiwan on Monday, both briefly prompting tsunami warnings, the Japanese Meteorological Agency said.

The first quake — a magnitude-6.8 — struck at 9:06 a.m. (8:06 p.m. EST Sunday; 0006 GMT Monday). It was followed about 10 hours later by a 6.5-magitude temblor.

Both were about 80 miles (130 kilometers) southwest of Ishigaki. The Japanese resort island is about 125 miles (200 kilometers) east of Taiwan and some 1,000 miles (1,600 kilometers) south of Tokyo.

After the first quake, Naoto Otake, a police official on Ishigaki, said there were no immediate reports of damage or casualties on the island, which has a population of 40,000.

"Nothing fell during the quake. Electricity, water and gas are all working," Otake said. There were damages reported after the second quake either.

There were also no reports of damage from the later quake.

Both temblors triggered the tsunami-warning system, and the meteorological agency said waves estimated to be about 20 inches (50 centimeters) high washed ashore in nearby areas shortly after each quake.

Japan is one of the world's most earthquake-prone countries. The most recent major quake in Japan killed more than 6,400 people in the western port city of Kobe in January 1995.

Taiwan's Central Weather Bureau said the first quake was felt there as well. There were no immediate reports of casualties or damage.