Blogger Roy Ngerng has been fired by his employer, Tan Tock Seng Hospital (TTSH), with immediate effect.

In a statement released on Tuesday afternoon, TTSH said it was terminating its contract with Mr Ngerng because of "conduct incompatible with the values and standards expected of employees, and for misusing working time, hospital computers and facilities for personal pursuits".

Mr Ngerng, 33, was employed on a yearly contract with TTSH for the past two years as a patient coordinator at the Communicable Disease Centre. The hospital said his supervisors found that "he was misusing TTSH time and resources to pursue personal and non-job-related interests".

It had issued him a formal letter in May warning him of his misconduct when his contract was up for renewal, but decided to give him a chance and renewed his contract. But Mr Ngerng had disregarded the warning and "continued to misuse company time and resources to access non-job related social media sites to pursue his personal interests", said TTSH.

It added that Mr Ngerng's recent public actions and conduct have caused the hospital "grave concern", citing the defamation suit that the blogger is currently embroiled in. The suit arises from a May 15 blog post in which Mr Ngerng alleged that Prime Minister Lee Hsien Loong is guilty of criminally misappropriating Central Provident Fund savings. He was asked to remove the post immediately, apologise, and give a written offer of damages and costs. Mr Ngerng took down the post and apologised.

Subsquently, Mr Lee's lawyer, Senior Counsel Davinder Singh, acccused Mr Ngerng of aggravating the "injury and distress" to the Prime Minister by repeating the libel through a video, other blog posts and e-mail. Mr Lee also rejected Mr Ngerng's offer of $5,000 as damages and began legal proceedings against him on May 29.

Noting that Mr Ngerng had publicly admitted to the defamation and that it was without basis, TTSH said his conduct was incompatible with the values and standards that it expects of its employees. "While our staff are free to pursue their personal interests outside work, they must conduct themselves properly, honourably and with integrity. In particular, they cannot defame someone else without basis, which essentially means knowingly stating a falsehood to the public".

TTSH added that his "neglect of duty and his improper public conduct" have compromised his work performance and are contrary to the high standard of integrity required of employees to maintain the vital trust between the hospital and the public. His disregard of the hospital's warnings and advice has made his continued employment "untenable", it added. Mr Ngerng will receive one month's salary in lieu of notice.

Posting on his Facebook page on Tuesday afternoon, Mr Ngerng said he had been expecting the news. "The stress of the court case has made it difficult for me to concentrate on my job. And my advocacy on the CPF has also taken a (toll) on my ability to do my job as well," he added.

He said he is proud of the campaigns he had launched at work and close relationships he has forged. "Though, I could have done a lot better over the past few months. My supervisors have been patient but they also have a responsibility to uphold and I respect that," he said. Mr Ngerng added, however, that it was a pity he is being "prosecuted" for speaking up on behalf of fellow citizens.