T

he Karo Police have closed down a tunnel at a South Korean joint venture hydro power plant following an explosion that killed six workers and injured seven others in Kutabuluh district, Karo regency, in North Sumatra on Wednesday.

Karo Police chief Adj. Sr. Comr. Viktor Togi Tambunan said that the closure was temporary and would be enforced until the National Police'€™s forensic laboratory had identified the cause of the explosion at the power plant operated by PT Wampu Electric Power (WEP), a joint venture between Indonesian company Mega Mandiri Power and two Korean companies, Korea Midland Power Co. Ltd. (KOMIPO) and POSCO Engineering Co. Ltd.

'€œToday the National Police'€™s forensic laboratory will enter the closed tunnel to investigate the cause of the explosion. The tunnel will be temporarily closed during the investigation process,'€ Viktor told The Jakarta Post, Thursday.

Earlier Victor told kompas.com that the victims may have been electrocuted after stepping into an electrified pool of water.

The bodies of the deceased were sent to their respective families for burial on Thursday while the injured had been sent to Efarina Etaham Hospital in Berastagi for immediate treatment.

Viktor said there had been 13 workers in the tunnel when the facility exploded and six died. The deceased have been identified as Anto Cibro, Jali Bako, Ruben Manurung, Hendra Sanjaya, Putra and Hamzah Haz alias Amar. Those injured were Panjang, Didit, Hermansyah, Mahrizal, Ramadhan, Ewin and Dam.

Viktor said the workers had been operating under the coordination of a Korean civil engineering company that worked together with WEP.

'€œWe have examined the company and several workers, as witnesses,'€ said Viktor, adding that no suspect had been named in the case so far.

Based on witness testimonies, he said, the company had dug the tunnel in an effort to speed up the operation of the power plant, which had been built to cope with the electricity crisis in North Sumatra.

Im Sung Hun, a representative of WEP, told police that the explosion at the tunnel occurred on Wednesday at 8:40 a.m. local time. He admitted to having seen smoke coming from the tunnel and had asked the operator to switch off the generator set. Not long after an explosion was heard.

'€œOther workers and I promptly went into the tunnel to help the workers who had been down there,'€ he told police.

Im Sung Hun said the workers in the tunnel had been installing frames.

He said that it had been very dark inside the tunnel as there was a lamp used for lighting and the electricity cable was nailed to the wall.

'€œAt the time of the incident the tunnel was wet. The water was as high as an adult'€™s knee. I thought the explosion may have been caused by an electrical short because there was smoke from the generator cable,'€ he told police during an interview at the Karo Police headquarters.

Before the accident occurred, the company had reportedly planned to close the tunnel until it dried. The 45 megawatt medium-sized power generator, when completed, will be the first independent hydroelectric power plant in Indonesia.

Last month, parts of North Sumatra and Aceh faced power outages after a fire caused damage to a high-voltage power line in Sicanang, Belawan, North Sumatra.

The line transmitted power from the Pangkalan Susu steam-driven electricity plant in Langkat regency, North Sumatra, and PLTU Nagan Raya in Aceh.