Jakarta. Indonesia's anti-corruption agency has expanded an investigation into alleged bribery and corruption in the processing of residence permits for foreign nationals, following the arrest of a senior immigration official and several others in a sting operation.

The Corruption Eradication Commission (KPK) said on Wednesday that investigators were conducting follow-up operations in Bali and West Java after detaining Ronald Arman Abdul, head of the Class I Non-Border Immigration Office in West Jakarta, and a number of other individuals on Tuesday night.

"Last night, the team carried out field operations in West Jakarta, and developments have led investigators to continue activities in Bali and West Java," KPK spokesman Budi Prasetyo told reporters at the agency's headquarters in South Jakarta.

Budi said the operations in Bali and West Java were linked to immigration processes handled in those regions but declined to provide further details while the investigation remains ongoing.

According to the KPK, the case centers on the issuance of residence permits for foreign nationals seeking to live in Indonesia. The investigation involves the processing of permanent stay permits, known as KITAP, and temporary stay permits, or KITAS.

Ronald and more than a dozen other individuals were taken into custody during the operation. The KPK has not disclosed how many suspects have been formally named or whether any foreign nationals were among those detained.

Budi said investigators were still determining the legal framework of the case, including whether the alleged misconduct involved bribery, extortion, or another form of corruption.

The anti-graft agency is continuing to question those detained and is expected to announce the results of its investigation after completing examinations within 24-hour.

The KPK said it would later disclose the chronology of the case, the alleged corruption scheme, the legal status of those detained, and details of evidence seized during the operation.

"The evidence secured includes cars, motorcycles, cash, foreign currencies including US dollars and Singapore dollars, as well as gold bullion," Budi said.