Bareskrim Reveals Suspected Cause of Transmission Cable Failure Triggering Sumatra Blackout

Jakarta — Deputy Chief of Bareskrim Police, Irjen Nunung Syaifuddin, has revealed the preliminary suspected cause of a transmission cable failure that triggered a widespread blackout across much of Sumatra on Friday (22 May 2026).

Nunung stated that initial suspicions point to technical and extreme weather factors, rather than sabotage. ‘The preliminary suspected cause of the transmission cable failure is still under investigation, with possible factors including mechanical issues from friction and wind, heat from loose connections causing gaps, or tension and swaying due to extreme weather,’ he said during a press conference at Bareskrim Police headquarters in Jakarta on Monday (25 May 2026).

Investigations are being conducted at transmission towers 175 and 176 in Desa Temino, Mestong District, Muaro Jambi Regency, Jambi province, which is suspected to be the origin of the Sumatra power system disruption.

‘Initial identification revealed that on Friday, 22 May 2026, at approximately 6:44pm WIB, a disruption occurred in the 275kV transmission line between Muara Bungo and Sungai Rumpeh in Jambi,’ he added.

This triggered a cascading failure, resulting in a widespread blackout across Aceh, North Sumatra, West Sumatra, Riau, Jambi, and parts of South Sumatra.

During field inspections, the team found the broken transmission cable near the transmission tower in Desa Temino. However, the physical structure of the tower was generally intact with no significant damage found.

This suspicion was bolstered by testimonies from local residents who reported hearing an explosion before the power cut. Among the witnesses interviewed was the local RT head, who lives near the transmission line.

At a joint case review, PLN also stated that the Sumatra power system was operating normally and integrated before the disruption occurred at 6:30pm WIB.