Three vehicles next to each other caught fire about noon Tuesday in a parking ramp that serves the University of Minnesota Medical Center, Fairview, officials said. No injuries were reported.

Because of the heavy smoke in the ramp on Delaware Street between Walnut and Harvard Streets, vehicles were prevented for about from entering or leaving the lot for about 90 minutes, and pedestrians were not allowed in during that time as well, said university spokesman Steve Henneberry.

The fire broke out in the engine compartment of a car on the ramp level between the fifth and sixth floors, and then reached the vehicles on each side of the burning car, said Minneapolis Fire Department Assistant Chief Charles Brynteson.

Extreme cold and heavy smoke presented challenges for fire personnel to battle the flames, Brynteson said.

There was no damage to the ramp itself, he added.

Paul Walsh