Monday marks 13 years since the Great East Japan Earthquake and Tsunami.

The disaster killed thousands and triggered a major nuclear accident, which has yet to be resolved.

People observed acts of remembrance since the early morning.

Daigaku Toshihiko lost five members of his family -- his wife, parents, brother and nephew. He comes on the 11th day of every month to remember them.

Daigaku said that 13 years have flown by since the earthquake and he wishes his family were still alive. He added that he would like to think they are watching over those who survived.

The magnitude 9.0 quake struck at 2:46 p.m. off the coast of the Tohoku region. It generated tsunami waves more than ten meters high, devastating Japan's Pacific coast.

Authorities say over 22-thousand people went missing or were killed, including those who died as a result of circumstances caused by the disaster.

The destruction forced hundreds of thousands more from their homes. Even now, over 29-thousand people still cannot return.

The tsunami also surged into the Fukushima Daiichi nuclear power plant, causing a triple meltdown.

Last year, the plant's operator -- the Tokyo Electric Power Company, or TEPCO -- began discharging treated and diluted water from the facility into the sea. The International Atomic Energy Agency has found the release consistent with international safety standards.

TEPCO is hoping to remove fuel debris from the reactors. It is said to be their biggest challenge, and the operation was recently delayed for the third time.

TEPCO is aiming to completely decommission the site by 2051. But multiple setbacks have thrown that timeline into question.