The investigation is designed to ascertain whether the blackout resulted from human error, Chief of the Public Relations Bureau of the National Police Brigadier General Dedi Prasetyo stated on Monday.
"It is being investigated to establish its cause. It could be the result of technical disruption, human error, or some other reason," he noted.
To this end, the police have established an investigating team, led by the department's criminal offence director, which will cooperate with state-owned electricity company Perusahaan Listrik Negara (PLN).
Related news: PLN apologize for blackout in Greater Jakarta
He desisted from divulging details on how long the investigation will last.
"It largely depends on the team on the field. For the time being, it was caused by disruption at the extra high-voltage power line between Pemalang and Semarang in Central Java," he pointed out.
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The blackout affected thousands of homes and public facilities in the areas of Greater Jakarta, Banten, and West Java on Sunday afternoon. The electricity went out at 11:48 a.m. local time.
The blackout also affected Jakarta's commuter train and MRT services.
PT PLN has gradually recovered the power supply. It has tendered an apology for the inconvenience caused and would conduct an evaluation to prevent recurrence of the incident. Related news: President discusses power supply recovery efforts
Related news: PLN gradually recovers electricity supply
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