Tsunami Anniversary: Four Years On, Photos Show a Still-Scarred Japan

Four years ago Wednesday, a magnitude 9.0 earthquake off the coast of Japan sent massive waves crashing onto the country's northeast region. The disaster killed more than 15,000 people and left thousands injured and missing.

Hundreds of thousands were left homeless by the tsunami, and the earthquake that caused it is one of the largest recorded since 1900, according to the U.S. Geological Survey.

The earthquake and tsunami also crippled the Fukushima Daiichi Nuclear Power Station, causing explosions and the release of radiation in the area. In the wake of the disaster, the Tokyo Electric Power Co. has been working to decommission the site, which has been cordoned off as an exclusion zone. At the same time, the country has begun the long process of recovery, though 250,000 residents are still displaced.

Cleanup efforts are ongoing, with Japan dedicating over $15 billion to reducing radiation levels around the plant in the last four years. Teams of workers "blast roads with water, scrub down houses, cut branches and scrape contaminated soil off farmland," Reuters reports.

In commemoration of the four-year anniversary, family members mourned, friends remembered and leaders paid their respects to the victims. Schoolchildren and adults around the country participated in readiness drills and training while others took part in rallies to denounce nuclear energy. Some attended large, organized memorials, while others chose to mark the day with a private gesture in honor those lost that day.