More than 60 firefighters were called to tackle the flames and six people were treated for smoke inhalation. Later a message was posted on the O2 Arena's website that the show is postponed.
"Due to a fire onboard a tour bus parked onsite this morning, the London Fire Brigade were called and the venue immediately evacuated... Unfortunately, due to this morning's fire on board one of the tour buses at The O2, tonight's Kings of Leon concert will now be postponed," the massage read.
"Whilst there is no damage to The O2 there is now insufficient time to rig the arena for tonight's performance. We are sorry for the inconvenience and we will announce a new date shortly," it added.