Para-athlete Abdullah Hayayei died after a metal throwing cage fell on him during training.
The United Arab Emirates thrower was training at Newham Leisure Centre for the World Para-athletics Championships in London.
Majid Rashed, vice president of the UAE International Paralympic Committee, confirmed “the throwing cage collapsed on the athlete’s head”.
Hayayei, 36, was pronounced dead at the scene at 17:20 BST on Tuesday.
The Health and Safety Executive and police are investigating the incident, which was witnessed by some of Hayayei’s team-mates and UAE staff.
“I can say the throwing cage collapsed on the athlete’s head – but how that happened, we can not say,” Rashed said on Wednesday.
The IPC said two of the athlete’s personal coaches were present but were not involved.
Hayayei, a father of five, was preparing to compete in the F34 class at the Championships.
“He was ambitious, he wanted to win medals for his country and for his family. He had a lot of dreams within the para-sports movement, ” Rashed said, adding that the UAE team will still compete in London.
“The athletes were very close to Abdullah, they trained in the same centre in the UAE. It’s really very difficult for all of us but we promised ourselves that we are going to continue and we are going to win something for Abdullah, bringing the best performance from the athletes.
“We are working with the athletes to get them in a better situation, obviously today will be better than yesterday, tomorrow we believe will be even better for them.”
The Metropolitan Police said emergency services “were called shortly after 17:00hrs on Tuesday… to reports of a seriously injured man at Newham Leisure Centre”.
It added: “At this early stage, it is believed the man was struck by a metal pole which formed part of training facilities at the centre.”
IPC president Sir Philip Craven said: “We are all truly devastated by this tragic news and the passing of Abdullah.”
Hayayei made his Paralympic debut at Rio 2016, finishing sixth in the javelin F34 and seventh in shot put F34.
London 2017, which starts on Friday, was to be Hayayei’s second World Championships. At the 2015 event in Doha, Qatar, he finished fifth in the discus F34 and eighth in shot put F34.
He was set to compete in the shot put, discus and javelin F34 events.
A moment of silence will be held in honour of Hayayei during Friday’s opening ceremony at London Stadium.