With the ruling Liberal Democratic Party's long-held plan to revise the pacifist Constitution becoming increasingly concrete and real, both backers and opponents of the supreme law marked its 68th anniversary Sunday with rallies to drum up support for their causes.

There was a growing sense of immediacy in both camps, as the LDP is aiming to have the Diet initiate the process for amending the U.S.-drafted Constitution in 2017, following the Upper House election in summer 2016, and then hold a referendum.

Around 30,000 people gathered at Rinko Park in Yokohama to argue against what they see as Prime Minister Shinzo Abe's efforts to steer the nation toward war.