Indonesian police on Thursday arrested three men with suspected links to Islamic State as part of an operation in the province of Central Sulawesi to capture the country's most-wanted man, state media reported.
The arrests came as the U.S. embassy in Jakarta issued an "emergency message" for U.S. citizens warning of potential security threats at tourist beaches on the island of Lombok surrounding the New Year's celebrations.
Counter-terrorism officials believe there are at least 1,000 sympathisers of the radical militants group across Indonesia. More than a dozen men suspected of planning bomb attacks over the holiday period were arrested in a series of raids recently, and the hunt is on for their ringleaders.
"This morning my team just reported that they had captured three more people," the Antara news agency quoted Central Sulawesi police chief Idham Azis as saying.
He gave no details of the arrests or the identities of the men, but said they are thought to be linked to militant leader Santoso, who has eluded capture for years and is holed up in jungles near Poso town in Central Sulawesi.
A National Police spokesman did not immediately respond to Reuters requests for comment on the Antara report.
Azis said a hunt for Santoso and about 30 of his followers would conclude on Jan. 9. He said seven suspected militants as well as two policemen and an army officer had been killed in the operation.
U.S. authorities on Wednesday noted arrests made by authorities in Turkey, Belgium and Indonesia in connection with suspected plots by ISIS operatives or sympathisers to launch attacks over the holiday, and said they were monitoring investigations.
Analysts say that Santoso, the first Indonesian to publicly pledge loyalty to ISIS, may be an inspiration for would-be jihadis and militants returning from fighting with the group in Syria.
However, some believe there is a bigger threat closer to the capital, Jakarta, on the populous island of Java, where most of the recent arrests were made, and say militants could increasingly target Westerners.
The U.S. embassy message did not spell out the security threat on Lombok, whose beaches are popular with Western holidaymakers, but it did mention specifically Senggigi Beach, the main tourist strip on the west of the island.