Part of a busy Chicago street has been closed after ice encased a fire escape on a high rise-building.

Police closed a section of a street near downtown around 5 p.m. Saturday because of falling ice. The street was expected to remain closed overnight.

Images show giant icicles hanging from a wrought-iron fire escape, which is roughly 20 stories tall.

Officials from Chicago's Buildings Department were working with the property managers of the building, which is home to a self-storage business.

The ice was believed to have been caused by a water leak. Chicago fire officials said the exact cause of the leak was unknown, but water spilled from a top floor to the front of the building.