Jurgen Klopp has expressed his sadness and shock after initially hearing the news that Borussia Dortmund, his former club, had been subject to a terrorist attack on Tuesday night.

The coach carrying the Dortmund team to Signal Iduna Park was hit by three explosions ahead of the side’s first-leg clash with Monaco in the Champions League quarter-finals, smashing some of the vehicle’s windows and leaving Spanish defender Marc Bartra with an injury to his hand and arm.

Klopp spent seven years at Dortmund, between 2008 and 2015, and led the German side to two back-to-back Bundesliga titles and one DFB-Pokal trophy.

Speaking for the first time after Tuesday night’s attack, the Liverpool boss admitted how “difficult” it has been for him.

"Everyone can imagine it was a really difficult moment for me," he said.

"I don't know how often I have been in that hotel down the years. I know exactly where it is on that road and a lot of my friends were on the bus.

"I tried immediately to get some information. I was really concerned, scared for them [the players], I was scared for everyone.

"I had contact with a few people but I didn't want to bother them with my silly questions so I was waiting like all the rest of the world for more information.”

Borussia Dortmund Team bus attack Show all 8 1 /8 Borussia Dortmund Team bus attack Borussia Dortmund Team bus attack Police stand near team bus of the Borussia Dortmund football club after it was damaged in an explosion in Dortmund, Germany Getty Images Borussia Dortmund Team bus attack Team bus of Borussia Dortmund is seen on a street after it was hit by three explosions in Dortmund, Germany EPA Borussia Dortmund Team bus attack According to reports, Borussia Dortmund's team bus was damaged by three explosions, as it was on its way to the stadium ahead of the UEFA Champions League soccer match between BVorussia Dortmund and AS Monaco EPA Borussia Dortmund Team bus attack Police escort Dortmund's players after the team bus of Borussia Dortmund had some windows broken by an explosion some 10km away from the stadium prior to the UEFA Champions League 1st leg quarter-final football match BVB Borussia Dortmund v Monaco in Dortmund, western Germany Getty Images Borussia Dortmund Team bus attack The match was postponed after a explosion targeted the Borussia Dortmun football team Rex Borussia Dortmund Team bus attack Police cars stand in front of the main entrance of the Dortmund training ground as Dortmund's players arrive one by one in their cars in Brackel, one day after the explosives attack on the Borussia Dortmund team bus prior to the UEFA Champions League 1st leg quarter-final football match BVB Borussia Dortmund v Monaco Getty Images Borussia Dortmund Team bus attack Fans hold posters 'You'll never walk alone' when Dortmund player Pierre-Emerick Aubameyang leaves the training ground of the team in Dortmund, western Germany, AP Borussia Dortmund Team bus attack A team bus arrives at the training grounds of Borussia Dortmund in Dortmund, German AP

The German also suggested that the game should not have been rescheduled for the day after the attack but said he “100 per cent understood” why it had gone ahead.

"The last thing I thought about [after hearing the news] was the game but when I watched the game yesterday and I can 100 per cent see both sides [why it went ahead].

"It's really, really difficult to find a date in this really tight schedule but I think everyone would have understood if they said they did not want to play it.

Diego Simeone reacts to the breaking news of the explosions near the Borussia Dortmund bus

"I was really proud of Dortmund, how they handled it and created this atmosphere.

"The game was not too important but when they played they tried to be at their best.

"But I saw it in the faces of my former players after the game and I saw the shock in their eyes and that was really hard. It will obviously take time to deal with it in a proper way.

"I'm pretty sure if some of the people who made the decision (to play the match) afterwards had been on the bus they would not have played the game but when you are not on the bus you cannot really imagine how it was exactly."

Jurgen Klopp spent seven years at Dortmund as manager (Getty)

And Klopp urged the football community to move on from the incident and return to normality, despite the distress and concern it has elicited.

“As human beings we all think about this but as long as we are not directly involved, it’s hard but life goes on,” he added.

“I see it like all in the world see it. We have to carry on. We will and we can. We can concentrate on football and training.