The operator of the decommissioned thermal power plant in Ulsan where a boiler tower collapsed last week, killing six workers with one other person still trapped underneath, apologized to the public for causing concern.

Reading from a statement at the site of the tower collapse on Thursday, Korea East-West Power Company President & CEO Kwon Myung-ho expressed his deepest condolences for the victims and their families, adding that his prayers are with them.

Kwon said all the company executives and employees are doing all that they can to provide support to the families and the victims, and to ensure recovery proceeds swiftly.

He promised to determine the cause of the accident and to prepare effective preventive measures.

Contractor HJ Shipbuilding and Construction CEO Kim Wan-sug, whose company undertook the demolition project, also issued an apology to the families, adding that his company is exerting full efforts toward finding the last missing worker.

The apologies come one week after the 63-meter tall tower collapsed during demolition operations, trapping seven out of nine subcontracted workers underneath the rubble.