BT Sport apologise for what Dortmund fans did amid Chelsea warning

Visiting supporters made their presence felt in west London as they let off smoke bombs before the Champions League game between Chelsea and Borussia Dortmund

BT Sport were forced to apologise for what a section of Borussia Dortmund fans did while watching their side take on Chelsea in the Champions League round-of-16. Supporters were keen to show their support for the German outfit by letting off a number of yellow smoke bombs at the start of the match.

This created quite a sight for those watching on from home, with the sandstorm effect making it difficult to see much of the action. Due to the poor quality of picture, commentator Darren Fletcher apologised to viewers at the top of the broadcast.

This action came despite a warning from Chelsea about what would happen to anyone who attempts to bring a pyrotechnic device into Stamford Bridge. On their website, a statement reads: "If you are found to be in possession of a pyrotechnic device either on the street or at the stadium, you will be arrested.

"At the start of the current season it was announced that in partnership with all of English football, there would be new measures and stronger sanctions against offenders to tackle anti-social and criminal behaviours, ensuring a safe and enjoyable matchday environment for all.

"At our stadiums and at all grounds in England, a new set of actions, which is backed by the Football Supporters’ Association, target activity such as entering the pitch without permission, carrying or using smoke bombs or pyrotechnics and throwing objects - as well as drug use and discriminatory behaviour.

"These acts are dangerous, illegal and have severe consequences. They have no place in football, or anywhere. At Chelsea we have long had a zero-tolerance approach to these forms of anti-social behaviour.

"All identified offenders will be reported to the police and prosecution could result in a permanent criminal record, which may affect their employment and education, and could result in a prison sentence.

"Those identified as carrying or using pyrotechnics or smoke bombs will be banned for a minimum of three years. These bans will be extended to accompanying parents or guardians of children who take part in these activities."