"One of the people killed bore resemblance to Santoso, and the body is being transported for identification by the family," Budi said
Indonesia's most wanted man, an Islamic State supporter, may have been one of two militants killed in a gunbattle with security forces in eastern Indonesia on Tuesday, the government said on Friday.
If confirmed, the death of Santoso, who was slapped by the United States with an official terrorist designation, would be a victory for President Joko Widodo, who made capturing him a top security priority.
Presidential spokesman Johan Budi said Santoso was believed to be one of two militants killed in an exchange of fire with police on Sulawesi island, where he was thought to be hiding.
"One of the people killed bore resemblance to Santoso, and the body is being transported for identification by the family," Budi said via telephone. Santoso's age was not known.
He had been hunted by Indonesian security forces for several years and pledged allegiance to the Islamic State group. His armed faction has attracted militants from other parts of Indonesia and several from the Uighur minority group in China's restive Xinjiang province.
Indonesia deployed thousands of police and military officials to scour the jungles of Sulawesi where Santoso and dozens of associates were believed to be holed up. Santoso was from the most populous Indonesian island, Java.
In March, the United States imposed a special terrorist designation on Santoso, blocking any U.S. assets he might have, banning dealings with him by Americans and opening the way for U.S. law-enforcement action against him.
The U.S. State Department said Santoso led the Mujahidin Indonesia Timur (MIT) that had carried out numerous killings and kidnappings in Indonesia over the past few years.