The start of the UK Athletics Indoor Championships in Birmingham was delayed by 90 minutes after the Utilita Arena was evacuated on Saturday morning.
West Midlands Fire Service said crews were called out after a cooker caught fire in a nearby flat.
Olympic bronze medallist and commentator Katharine Merry posted on X:, external “Not made it into the Utilita Arena yet. It’s been fully evacuated due to a fire. Fire brigade here and smoke coming from the top floor.”
UK Athletics said on social media that spectators “would experience a delay” to the opening of the venue.
The two-day championships are being shown live on the BBC.
Olympic stars Katarina Johnson-Thompson and Georgia Hunter Bell are among those competing for British titles in Birmingham this weekend.
Johnson-Thompson, who ended her wait for an Olympic medal with heptathlon silver at Paris 2024, will participate in the 60m hurdles and shot put events.
Olympic bronze medallist Hunter Bell will seek to defend her British indoor 1500m title.
