A city official in San Francisco is calling for extensive reports into the integrity of facades in the city’s downtown after a recent storm caused windows from multiple high-rises to be damaged.

According to the San Francisco Department of Buildings and Inspections, four buildings in downtown San Francisco suffered glass failure during a high-wind storm last week. The Millennium Tower suffered one broken window, as did 1400 Mission and 50 California, while the Salesforce East building suffered one broken window on every floor from floors 11 through 30.

As a result of the glazing failures, shards of glass were scattered across Mission Street, posing a hazard to pedestrians below. City officials have since directed building managers to secure impacted windows and commission professionals to ensure all buildings are safe, stable, and secure.

In the meantime, San Francisco supervisor Aaron Peskin told ABC7 News that the city should mandate comprehensive engineering reports for all downtown buildings.

“Some of these buildings are modern buildings,” Peskin told ABC7. “Some of these buildings are over 50 years old. There seems to be no pattern here.”

The Department of Buildings and Inspections has issued notices of violations to all affected buildings, which requires them to secure the broken windows, replace the glass as soon as possible, and have all windows in the buildings evaluated by a licensed engineer within the next 14 days, ABC7 reports.

While investigations have not determined why glazing in the towers could not withstand last week’s windy conditions, civil engineer Steven Viani speculates that faulty seals on the windows were exploited by wind pressure to cause the failures. “Maybe the seals weren't in as good a condition as they should have been, or maybe not even properly set in there,” Viani told ABC7.