TOKYO – Prime Minister Shinzo Abe pledged to boost rebuilding efforts as the country marked the third anniversary Tuesday of a devastating earthquake and tsunami that left nearly 19,000 people dead, destroyed coastal communities and triggered a nuclear crisis.

Japan has struggled to rebuild towns and villages and to clean up radiation from the meltdowns at the Fukushima Daiichi nuclear power plant. Reconstruction plans are finally taking shape, but shortages of workers and materials are delaying the work.

The disasters killed 15,884 people and left 2,636 unaccounted for on its northeastern coast. The country has earmarked $250 billion for reconstruction through March 2016.

Three years later, almost 270,000 people remain displaced from their homes, including many from Fukushima who may never be able to return home due to radioactive contamination.

During a ceremony in Tokyo, there was a minute of silence to mark the moment, at 2:46 p.m., when the magnitude 9.0 earthquake struck off the Tohoku coast. It was the strongest quake in Japan's history.

"We must further speed up the reconstruction so that everyone affected by the disasters can return to ordinary life," Abe said.

In Fukushima, reconstruction has lagged further behind. Several towns are still off-limits due to high radiation.

The plant is still plagued by frequent leaks of radioactive water, triggering questions about whether its operations are really under control.

Yukari Tanaka, who lived near the Fukushima plant, said she couldn't look for her father after the tsunami because she was ordered to evacuate. Weeks later, he was found dead.

"I never forget how I regretted that I had to evacuate, leaving my father behind," she said.