Japanese officials have formally asked their Philippine counterparts to extradite four Japanese citizens. The four are suspected of orchestrating a series of crimes across Japan from inside Philippine detention centers.

Japan does not have an extradition treaty with the Philippines.

Investigators say the group may be linked to robberies across 14 prefectures. They allegedly recruited people in Japan through social media and provided instructions through chat apps using aliases like "Luffy" or "Kim."

In one incident, a 90-year-old woman was robbed and murdered inside her home in Komae City, Tokyo.

The suspected ringleaders include Watanabe Yuki. He is believed to have contacted accomplices with a smartphone that had been smuggled into a Philippine detention facility.

The Philippines' Justice Secretary Jesus Crispin Remulla told a news conference on Monday that he hopes to settle the matter before President Ferdinand Marcos Jr. visits Japan. The president is scheduled to make the trip in the first half of February.