TOKYO -- Japan is marking the 10th anniversary Thursday of the earthquake, tsunami and nuclear disaster that hit the northeastern region, where many survivors' lives are still on hold.

People, some carrying bouquets, walked to the coast or graves to pray for relatives and friends washed away by the tsunami. Emperor Naruhito and Prime Minister Yoshihide Suga were among those observing a moment of silence at 2:46 p.m. -- the minute the shaking started -- and were to speak at the memorial service later.

The magnitude 9.0 quake that struck on March 11, 2011, was one of the biggest temblors on record and set off a massive tsunami that swept far inland, destroying towns and causing meltdowns at the Fukushima Daiichi nuclear plant. More than 18,000 people died, mostly in the tsunami, and nearly half a million people were displaced.