Justin Bieber apologized to his fans in London who were devastated when the singer showed up almost two hours late for the first stop of his “Believe” tour.

Bieber sparked outrage Monday from his young fans, and their parents, when he appeared onstage at London’s O2 Arena at 10:30 p.m, the Associated Press reported. He apologized to concertgoers in a series of lengthy Twitter posts.

“since i have been here it hasnt been easy with the press at times but I have loved it. so let me say this... last night i was scheduled after 3 opening acts to go on stage at 935 not 830 but because of some technical issues i got on at 10:10..so... i was 40 min late to stage. there is no excuse for that and I apologize for anyone we upset. However it was great show and Im proud of that and tonight we will run on time and look forward to putting on an amazing show for everyone in attendance. my relationship with the media is not always easy but im trying. Im all about the music and the performance and i respect my fans. i never have any intent to upset or let anyone down. and Im not okay with things being exaggerated. once again sorry for anyone upset. now we have a show to do today and Im gonna focus on the positive and put on a great show tonight here in London NIGHT 2 at the 02 is gonna be even better. get ready. Thanks.”

His start time was scheduled for 8:30 p.m., the AP said, and many fans waited for hours to see Bieber perform. One fan, Sophia Lee, told E! News that “everyone was kept waiting not knowing anything. All they did was [keep] playing Michael Jackson songs.”

Some fans ended up leaving and not catching the “Baby” singer.

"There were teenage girls crying outside," Louise Cooper told the AP after buying her 9-year-old daughter tickets as a birthday present. "The ladies sitting with us had to leave after 20 minutes and they had spent 70 quid (70 pounds, or $106) each on a ticket, which is really bad. It's one thing if your demographic is 50 year olds, but his demographic is lots of little girls who need to go home and go to bed."

Another fan said people began to boo around 9:30 p.m., when Bieber was still a no-show. Several fans called the venue’s lack of a prompt apology “disgusting.” It wasn’t until later that arena officials tweeted, “Sorry to all the Justin Bieber fans for the lateness of his show tonight. The Tube will still be running when the show finishes.”

The Telegraph reported Bieber finally started his set at 10:23 p.m. and finished at midnight, breaking the O2’s noise curfew. The newspaper also noted it caused mass transportation issues for the 20,000 fans attending the show. Wayne Parsonage and his wife had to leave with their 8-year-old daughter, Chloe, after seeing the singer for only 25 minutes, since the last train was at 11 p.m.

"Chloe was very disappointed and she didn't understand why we had to leave early," he told the Telegraph.

The AP noted that Bieber had been spotted out and about in London during his three-night tour in the city.