The Leicester City owner's helicopter has crashed in a car park outside the club's ground as it left the stadium following a Premier League match.
Vichai Srivaddhanaprabha was in the helicopter when it came down at about 20:30 BST on Saturday, a source close to the family has told the BBC.
One witness said he saw Leicester player Kasper Schmeichel run out of the stadium towards the scene of the crash.
It is not known how many other people were on board the helicopter.
Leicester had drawn 1-1 against West Ham United at the King Power Stadium.
The game kicked off at 17:30 and finished about one hour before the helicopter took off.
Under Mr Srivaddhanaprabha's ownership, Leicester City won the Premier League in 2016, having started the season as 5,000/1 outsiders.
Leicestershire Police said officers were working alongside the other emergency services, the Air Accidents Investigation Branch (AAIB) and Leicester City FC to establish the circumstances of the collision.
In the early hours of Sunday the force tweeted that the AAIB, which said it had sent a team to the stadium, was leading the investigation.
Leicester City said the club was assisting police and emergency services and would issue a more detailed statement in due course.
BBC Online
BDST: 1249 HRS, OCT 28, 2018
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