A senior work safety official's grin at the site of a deadly traffic accident in Shaanxi province has become a nightmare haunting him.

Yang Dacai, 55, head of the Shaanxi Provincial Bureau of Work Safety, was seen to be grinning in a photo taken after he arrived at the scene of a deadly traffic accident on Sunday in Yan’an, Shaanxi. Thirty-six people were killed when a sleeper bus rammed into a truck carrying a tank of methanol and caught fire.

The photo triggered an online wave of criticism among netizens.

The criticism grew louder when photos of Yang wearing five different watches, including Rolex, Mont Blanc and Radar, were posted online.

Many bloggers questioned how he could afford the costly timepieces and called for a corruption investigation.

On Wednesday night, Yang went online and apologized for the "relaxed" grin, saying that he was just trying to cheer people up after a long trudge to the accident site.

And he defended his innocence regarding the watches, saying he had "used legal income" to buy them over the past 10 years and he had reported the situation to the Party’s disciplinary organization.

Despite this, the Party Discipline Inspection Commission of Shaanxi has started an investigation on Yang, who would be punished if he is found to have violated disciplines or committed corruption, cnwest.com, an online news portal of Shaanxi, reported on Thursday.

Though he went online "late", at 9 pm, to give his explanation, his 13 blog entries, had been commented on more than 12,000 times by Thursday afternoon.

On Thursday, however, new photographs of Yang wearing four other watches appeared online.

Experts identify those watches as two Rolexes, a Diagono by Bulgari and a Constellation by Omega.

Kang Weikai, chief watch editor at Beijing’s Life Style magazine, said on his micro blog that one of the Rolexes is from the Explorer II series, and lists for 58,900 yuan ($9,300).

Morris Gao, a respected watch expert with the online Watchstore Forum (watchstore.com.cn) said the other Rolex is from the classic oyster bracelet collection, a gold watch worth more than 120,000 yuan.

"Conservatively estimated, the nine watches together cost more than 300,000 yuan at least," Gao said.

"Owning such a collection of luxury watches seems over the top for a government official."

Many netizens left messages on Yang’s micro blog asking whether he had told the truth and how he explained the additional watches.

Yang could not be reached for comment on Thursday.

An official in the general office of Yang’s bureau said they have noticed a growing number of people questioning how Yang could afford the watches.

She said she could not confirm whether the pictures are genuine and said Yang answered the questions the night before and was not available for comment.

Some of the newly updated pictures are marked as coming from the Hanzhong city government or urban and rural planning and construction website of Hanzhong, also in Shaanxi.

Yang was deputy mayor of Hanzhong from 2004 through 2011.

Dang Haibo, an official with the bureau’s human resources department said Yang is very "low-profile".

Wednesday’s online explanation made Yang one of the first to use social media to handle a public relations crisis, said Shen Yong, senior publicity official of Foshan, Guangdong province.

The interaction has drawn mixed reactions.

Guo Hongjun, a musician, wrote that Yang’s online explanation was useless because the key to managing a public relations crisis is to speak the truth and be frank from the beginning.

Zhang Jianping, a teacher in Nantong, Jiangsu province, supported Yang, saying he was not interested in challenging officials’ credibility. "My real concern is whether the official would step forward to face the challenges."

wanghuazhong@chinadaily.com.cn