Jakarta. Jakarta Police are tightening security across international schools following a series of bomb threats targeting campuses in North Jakarta and South Tangerang this week. While all incidents turned out to be hoaxes, authorities said they are intensifying patrols to reassure parents and students and prevent further disruption.

North Jakarta Police on Thursday conducted a full sweep of the North Jakarta Intercultural School (NJIS) in Kelapa Gading after receiving an email threat demanding $30,000 in cryptocurrency. No explosives were found, but the incident prompted the Jakarta Metropolitan Police to order heightened surveillance at all schools, particularly those with open access policies.

“After the incident, we received instructions to conduct both visible and undercover security operations at all schools, especially international ones,” North Jakarta Police Chief Commissioner Erick Frendriz said. “The goal is to keep students, teachers, and parents calm while ensuring that learning activities continue as normal.”

Police are also investigating possible links between the NJIS case and similar threats sent on Tuesday to Nanyang School in Pagedangan, Tangerang Regency, and Mentari Intercultural School in Pondok Aren, South Tangerang, both of which temporarily suspended classes as bomb squads cleared the premises. No explosives were found in either location.

Erick said the police’s Cyber Directorate is tracing the digital trail of the suspect, noting that the ransom wallet address provided in the email was invalid and not tied to any recognized crypto exchange in Indonesia, an indication that the threats were likely intended to spread fear rather than extort money.

“We are conducting an in-depth investigation and hope to identify the perpetrator soon,” Erick said, urging the public not to circulate unverified information.

To prevent further incidents, police have stationed officers at six international schools in North Jakarta, including NJIS and Jakarta Intercultural Academy, working closely with school security teams to strengthen protection measures.