TOKYO: Japanese in Tokyo and along the northeast coast are marking the seventh anniversary of the tsunami that took more than 18,000 lives and triggered meltdowns at the Fukushima nuclear power plant. Residents in coastal towns observed a moment of silence Sunday after sirens wailed at 2:46 p.m., the moment the magnitude-9.0 offshore earthquake that triggered the tsunami struck on March 11, 2011. The tsunami overwhelmed sea walls and washed away buildings, cars and entire neighborhoods as it swept inland. Prime Minister Shinzo Abe said at an official ceremony in Tokyo that reconstruction is making steady progress, but more than 70,000 people are still displaced from their communities and many will never be able to return. Cleaning up the still-radioactive nuclear plant remains a daunting challenge that will take decades.