The CEO of a South Korean lithium battery maker that was struck by a fire that killed 23 people in June has been arrested after a court approved a warrant on allegations of violating industrial safety law, a judge said on Thursday.

Park Soon-kwan, the CEO of Aricell, which is majority owned by S-Connect (096630.KQ), opens new tab, apologised after the fire but said at the time the company had followed all required safety precautions and training for staff.

The Suwon District Court, which has jurisdiction for the city of Hwaseong where the factory is located, approved the warrant for Park's detention late on Wednesday due to the gravity of the allegations against him, a public affairs judge said by telephone.

The court also approved a detention warrant for Park's son, who is an executive at the company, she said.

Park's lawyer could not be immediately reached for comment.

Entering the court for a hearing on Wednesday, Park did not answer reporters' questions about the charges against him but said "I'm sorry," television footage showed.

Authorities investigating the fire released a report on Friday saying a rush to meet a supply deadline and a lack of action to address signs of dangerous quality defects in batteries that had been produced led to the fire.

Hiring temporary workers who did not receive proper safety and emergency escape training to make up for a backlog of production contributed to the large number of casualties, police and labour ministry officials said.