Ata Safdar, the head of British consumer goods giant, Reckitt Benckiser in Korea and Japan was smacked over the neck while he tried to apologise for his company's involvement in the use of humidifier sterilisers that were linked to deadly lung injuries. Safdar, undeterred by the assault, continued his apology and bowed several times to the audience.

The news conference held in a Seoul hotel on 2 May, is the first public acceptance of responsibility by the firm for its role in the controversy since 2011. According to Reuters, a total of 92 people were believed to have died from causes related to the use of the humidifier products. Not all of the humidifiers were however marketed by Oxy Reckitt Benckiser, the group's South Korean arm at the time.

"Today's apology, was about acceptance of responsibility for the harm that Oxy HS [humidifier sterilisers] has caused. This is the first time we are accepting the fullest responsibility, and we are offering a complete and full apology," he said.

"We were late, five years have passed, we are also apologising far too late. This is what we are apologising about," Safdar said. As he spoke, a man came on stage, shouted at Safdar and then slapped him at the back of his neck.

Products produced by Reckitt Benckiser - Vanish, Finish, Dettol and Harpic - are seen in London
Products produced by Reckitt Benckiser - Vanish, Finish, Dettol and Harpic. Reuters

"This is heartbreaking. I apologise again. I would request that I am allowed to finish my statement please," he asked. Among those in the audience, included victims and their families, including a 13-year-old boy who has to use an oxygen tank to breath.

Safdar said some 178 users of its products are believed to be among those suspected to have been linked to lung ailments. He also outlined a plan to set up a compensation panel.

South Korea has said that since 2011, around 530 people have submitted claims over the humidifier sterilizers, marketed by Oxy Reckitt Benckiser and similar products by other companies. South Korea is believed to be the only country where the products were sold.

Last month, the company issued a written statement apologising for failing to communicate more quickly to the victims and their families. It has also set up a 5bn won (£3m, €3.82m, $4.41m) "humanitarian fund". This is in addition to the 5bn won fund set up in 2014, Reuters noted.

According to Sky News, many of the victims were women and children, who use humidifiers during South Korea's dry winter season. The issue with the products emerged in 2011 when four pregnant women died of lung problems and the government found "significant association" with the sterliisers.