SINGAPORE - StarHub and M1 have accepted Singtel group chief executive Chua Sock Koong's public apology made late Thursday night for a smear campaign that ran last year.

StarHub's chief executive officer Tan Tong Hai said in a statement: "We note and accept Singtel group CEO's apology."

An M1 spokesman said: "We accept Singtel's apology and will not be taking further action."

The Infocomm Development Authority is still investigating into whether Singtel had breached Singapore's Telecom Competition Code, imposed on all telecommunications licensees.

Last Saturday, blogger Wendy Cheng, better known as Xiaxue, posted on her website a leaked 2014 e-mail from social media agency Gushcloud in which it gave instructions to its bloggers to complain about StarHub and M1's network connections and services.

By doing this, it hoped to promote a Singtel youth mobile plan, with Gushcloud's bloggers receiving up to $4,000 in cash incentives, among other benefits, for successful sign-ups.

Ms Cheng also posted many samples of these published online complaints targeted at StarHub and M1.

Singtel apologised on Tuesday for the marketing campaign last June that disparaged its rivals.

Singtel explained that its marketing standards that forbid negative campaigns had not been followed, and that the incident was an "isolated" one.

On Thursday night, the telco posted a second apology, this time on Facebook. It was signed off by Ms Chua and she pledged that the company would reinforce its "high standards and values" internally and on its business partners.

Singtel also terminated Gushcloud's service and said that the employee involved in the campaign is no longer with the company.

When contacted today, the telco declined to provide details, including whether the employee in question was sacked or if he had already left the company.