TMZ.com

Firefighters in London yesterday got an eyeful of Madonna, when a blaze broke out in the building above her pilates studio. Talk about burning up!

Madge, who was rocking a Barney-inspired sweatsuit, was caught leaving her St. John's Wood gym -- as a fire burned in the building three floors up. Sweat it!

Firemen on scene did a double-take when the Material Mom breezily walked out of the studio -- not even noticing the smoke coming from the building -- and hopped into her waiting Audi.