A clip of a randy couple having sex in a Vienna underground has become an internet sensation.The camera phone video footage shows a young man having intercourse with a woman in a train of the Wiener Liniens U1 U-Bahn service. While he is standing with his pants down, his partner is on one of the carriage’s seats.The horny pair do not seem to be bothered by the soaring number of passengers filming their actions on their mobile phones.Footage of the incident has been watched hundreds of thousands times on video platforms like YouTube. Some platforms immediately deleted the clips after being put online for violating their conditions of use.Answer Lang a spokesman for Wiener Linien, the Austrian capitals public transport agency said today (Thurs): “This could have been the first time such a thing happened on one of our trains. No one reported the couple to the police. Its impossible to avoid such incidents.”Wiener Linien made headlines in less amusing context earlier this month when more than 200 passengers got stuck in a U4 line train in a tunnel near Schottenring station after a power outage for two hours.The companys error management guidelines say that the evacuation of a faulty train must not take longer than 15 minutes.Wiener Linien decided to offer eight-day rider tickets costing 28.80 Euros to the affected customers, but controversially dismissed appeals to compensate them financially.