Leicester City manager Claude Puel has labelled Saturday's helicopter crash outside the King Power Stadium as "a tragedy for the club".
An aircraft belonging to chairman Vichai Srivaddhanaprabha came down in a car park shortly after take-off at about 20:30 local time, around an hour after Puel's side claimed a 1-1 draw against West Ham in the Premier League.
There have been unconfirmed reports that Srivaddhanaprabha was on board and it is unclear at this stage whether there are any survivors.
Leicestershire Police confirmed the Air Accident Investigation Branch is leading an investigation, while the club are assisting the police and emergency services, with a more detailed statement to follow once further details have been established.
Some speculation on Saturday suggested Puel himself might have been on board but the 57-year-old confirmed he was safe in a telephone conversation with Jacques Vendroux of Radio France, in quotes reported on the Franceinfo website.
"It's a tragedy for the club," he said. "I think very strongly about the victims and their families.
"I wanted to reassure everyone who cares about me, I'm terribly sad but I'm fine."
Srivaddhanaprabha bought Leicester in August 2010 and was named chairman in February 2011. The Thai businessman oversaw the Foxes' remarkable Premier League triumph in 2015-16.
As the wait for further news about the crash continued on Sunday, dozens of fans gathered at the King Power Stadium to lay floral tributes.
Leicester's scheduled FA Women's Championship fixture against Manchester United has been postponed.
