One of the tweets Kotsopoulos posted yesterday. A minute or so later he derided a casual employee he was working with at the store that day. "She changes music & puts on this filthy emo music. Literally want to neck myself," he writes. But his harshest barbs were reserved for customers. "To top it off i'm serving mentally retarded people who buy phones and have no clue how to use them. Asking me to message people for them. Creating contacts for them and dictating me to enter the contact names then screaming at me when I spell it wrong. Speak English idiot!" His rage continued on to Facebook, where his profile was open to the public. He wondered in a post yesterday whether "the local mental institution shut down today or something". "If I have to serve another person who repeats everything I say like a parrot or I have to explain the same thing to them more then 6 times somebody is going to cop a pimp slap backhand," he wrote.

One of the tweets Kotopoulos posted yesterday. "It's starting to get extremely frustrating right now. Don't buy a phone IF you have absolutely no idea how to even use the most simple of functions." It doesn't appear to be a momentary lapse of judgment as in February this year he tweeted that "some European women would be drop dead gorgeous if they didn't open their mouth to speak". Another of the tweets Kotsopoulos posted yesterday. "Ugliest voices I've heard in my life. Served an amazing Brazillian with a booty but when she opened her mouth eeeeeeeeeeerrrrrrrrrrrr....," he continued.

On his LinkedIn page Mr Kotsopoulos says he has been Vodafone's "social media expert" since November last year. He also lists his job at the Vodafone George Street store in Sydney where he has worked since October 2010. On Facebook and on Twitter he lists another role at Vodafone, "TNT Ambassador". He describes this as: "Front-line for technological queries for Vodafone AU. Lending my ideas on how to sell the latest phones on the market as well as checking out what's to come." He writes on LinkedIn "since I am apart of the Y Generation I have the knowledge in technology and handsets that allows me to generate content for the [Vodafone] blog". Of his retail sales experience at Vodafone, he writes that he has "learnt to have a certain etiquette when it comes to communicating" with customers. A Vodafone spokesman said the telco welcomed feedback from its customers and employees in any forum but was "disappointed" with Mr Kotsopoulos' views, which did not reflect those of the company.

"We will be following up with Mr Kotsopoulos on why he expressed these views," the spokesman said. Of Mr Kotsopoulos' Vodafone "ambassador" claim, the telco said it ran a program for retail staff called "Talking New Technology" that encouraged staff to give feedback on the technology the company sells. Vodafone has referred to people in this group as "TNT ambassadors". Mr Kotsopoulos also works for video game review site OXCGN.com. On his Facebook "about" section he lists the things he hates. These include Australia ("and the scum people that populate it") and the internet ("full of keyboard heroes, idiots who think they are actually something special coz they can swear"). Social media expert Tiphereth Gloria, from VML Australia, said Mr Kotsopoulos' social media experience meant he had no excuse for not knowing what he was doing. "It's like he wants people to see his rants and he probably thinks his managers are not going to notice or he's egotistical enough to think he can get away with it," she said.

"I don't know what their [Vodafone's] internal and external social media policies are, but some of the things he is saying publicly are racist and sexist and hardly appropriate for someone who's identifying themselves as working for a corporation." Ms Gloria recommended companies have clear social media policies that link to their general HR policies. She said spot checks on personal social media channels should be carried out by managers when employees have identifying bios showing the company details. Anthony Mason, manager of digital research and analysis at social media monitoring firm SR7, said this incident would damage the reputation of Vodafone in the eyes of consumers, business clients and employees. "Incidents such as these should further crystallise the high potential for social media risk, particularly stemming from employee activity, to damage corporate brands," he said. "This risk is not limited to brand damage either; employees are the key source of corporate information leakage on social media platforms."

Mr Mason said companies could implement intelligence monitoring tools that detect risky posts or accounts and provide early warnings. In a new comment provided after publication of this article, Vodafone said it had suspended Kotsopoulos pending a full investigation. It apologised for anyone who was offended by the comments, which the telco said it was "appalled" by and "clearly contravene Vodafone social media policy and guidelines for acceptable conduct by employees".