Indonesian security forces are regrouping to launch a more aggressive campaign to hunt for the country's most-wanted man, police said Monday after months of fruitless searching in the jungles of Sulawesi Island.

President Joko "Jokowi" Widodo has made the arrest of Santoso, Indonesia's most high-profile backer of Islamic State, one of his national security priorities and had given security forces until Saturday to arrest him.

But Santoso, who has been on the run for more than three years, has proven to be more difficult to catch than expected.