Okinawa Gov. Takeshi Onaga died Wednesday evening at age 67 following hospitalization related to pancreatic cancer.

The death of the governor, who had been ill for many months and who underwent surgery in April to remove a cancerous tumor, comes just days after he ordered local officials to start the process of retracting the previous governor’s 2013 approval of a landfill project needed to relocate U.S. Marine Corps Air Station Futenma to the Henoko coastal district in Nago, in northern Okinawa, from a densely populated area in Ginowan, central Okinawa.

In October 2015, Onaga revoked his predecessor Hirokazu Nakaima’s 2013 approval of Tokyo’s request for related landfill work in Nago, saying it was legally flawed. But the Supreme Court ruled against Onaga’s position in December 2016, allowing the central government to resume construction last year.

The move had been the latest, and possibly last, in the long-running battle between Okinawa residents and politicians who oppose the new facility and the central government, which is pushing for it.

Onaga, a former mayor of Naha, ran against incumbent Nakaima in the 2014 election, beating him by nearly 100,000 votes in a three-man race. Onaga drew support from a broad coalition of traditional groups opposed to the U.S. military presence in Okinawa and local businesses that were not necessarily opposed to the U.S.-Japan security treaty but did not want Henoko.

Onaga’s death is expected to deal a blow to the anti-Henoko movement, but it was not immediately clear Wednesday night what would become of his most recent effort to stop the project. The Defense Ministry’s Okinawa Defense Bureau has already completed construction of the related seawalls, and landfill work could begin this month.

“His death is very regrettable, and his supporters will be discussing Thursday what the next steps should be,” said Satoshi Taira, an Okinawa anti-base activist.

In a statement to the media Wednesday night, Defense Minister Itsunori Onodera expressed his regrets and condolences at the news of Onaga’s death.

A scheduled rally in Okinawa Saturday against Henoko by Onaga’s supporters was still on as of Wednesday evening, Taira said.

Just prior to Onaga’s death, Okinawa Vice Gov. Kiichiro Jahana told reporters he would temporarily assume the governor’s duties. Jahana is considered by Onaga’s supporters to be a strong opponent of Henoko.

The governor’s death also leaves the anti-Henoko movement without a candidate in the next gubernatorial election, which had been scheduled for Nov. 18. A clear successor has not yet emerged, Taira said.

Under the election law, the gubernatorial election to choose the Onaga’s successor must be held within 50 days.

The Liberal Democratic Party’s Okinawa chapter decided last month to field Ginowan Mayor Atsushi Sakima, who has been less confrontational with the Abe administration over the Futenma relocation to Henoko.

Information from Kyodo added