Protesters marched in Okinawa on Friday, calling for the scrapping of a controversial U.S. military base relocation project, ahead of the 46th anniversary Tuesday of the prefecture’s reversion to Japan from U.S. control.

Some 820 participants started the three-day peace march in the prefecture, which hosts the bulk of U.S. military bases in Japan, as Tokyo pushes forward with a plan to relocate U.S. Marine Corps Air Station Futenma from the densely populated city of Ginowan to Henoko in the coastal area of Nago. Local residents have urged authorities to scrap the plan and relocate the base outside the prefecture.

The march was split into two routes, with one starting in front of the gate of U.S. Marine Corps’ Camp Schwab in Henoko, where an anti-base sit-in protest continues, and another starting in front of the Okinawa Prefectural Government building in Naha.

At a ceremony held at the building, Naha Mayor Mikiko Shiroma expressed resentment and frustration over base-related incidents.

“Crimes and accidents linked to bases continue to occur with no end in sight,” he said.

Local residents have long been frustrated by issues related to U.S. bases in Okinawa. The prefecture comprises only 0.6 percent of Japan’s total land mass, but hosts around 70 percent of the U.S. military facilities in the country.

Midori Tsuchiya, a 62-year-old demonstrator from Hiroshima, said, “Through the march, I want to pray for peace and protest against bases to prevent a repeat of a tragedy like the Hiroshima atomic bombing.”

Both groups of protesters will march toward the city of Ginowan, whose residential area is occupied by the Futenma base, to hold a peace rally Sunday.

The annual rally was first held in 1978 to protest against the continued presence of the U.S. bases in Okinawa even after it was returned to Japanese control in 1972. Okinawa had been under U.S. control since World War II.

Similar marches will be staged on Okinawa’s Miyako and Ishigaki islands on Saturday and Tuesday, respectively.