Two strong earthquakes (search), one magnitude 6.9 and the second magnitude 7.3, rattled western Japan within hours of each other Sunday night, injuring 14 people, shaking buildings in Tokyo and triggering tsunami waves.

Damage and injuries appeared to be limited because both quakes were far off Japan's coast, and the region shaken most strongly by them was a sparsely populated rural area, Wakayama, 280 miles west of Tokyo (search).

But tall buildings in Osaka, Kyoto and Nagoya shook, while buildings swayed in Tokyo.

The first quake, with a 6.9-magnitude quake, struck shortly after 7 p.m., centered 70 miles southeast off the Kii peninsula and 6 miles beneath the Pacific Ocean floor. Kyodo News reported that five were hurt in the first temblor.

The second temblor, of magnitude 7.3, struck about five hours later, centered about 80 miles southeast off the coast of Kochi prefecture (state) also 6 miles below the seabed. Public broadcaster NHK reported nine people were injured.

Tsunami -- waves triggered by seismic activity -- were recorded along the Pacific Coast, the largest being 3 feet high.

The Meteorological Agency issued fresh tsunami (search) warnings after the second quake, prompting several coastal towns in Mie prefecture (state) to order residents to evacuate, public broadcaster NHK reported.

The first quake was likely a precursor to the second, NHK quoted Katsuyuki Abe, a professor at Tokyo University, as saying.

"It is important for us to closely observe the seismic activity in the area off the Kii peninsula," said Masahiro Yamamoto, manager of the earthquake and tsunami section of the Meteorological Agency, at a televised news conference. "We need to analyze the movements of the earth's crust. This will take some time."

A high-speed train service was suspended for about 10 minutes, Kyodo reported. Local commuter lines serving western Japan were also temporarily halted, the news agency said.

Most of the injured suffered broken bones or bruises from falling or from being hit by objects, news reports said.

The Meteorological Agency initially said the first quake had a magnitude of 6.8, but later revised it to 6.9.

Japan, which rests atop several tectonic plates, is among the world's most earthquake-prone countries.

A magnitude 7 quake is capable of causing widespread, heavy damage.

In 1995, a magnitude-7.2 quake in the western port city of Kobe killed 6,400 people.