"Sounds scary, a big building like that, with a lot of potential for something to go wrong," said one passerby to KCBS Radio. "It should be investigated and looked over so somebody knows exactly what needs to be fixed."
A spokeswoman for Boston Properties, the owner of Salesforce Tower, told the San Francisco Chronicle the cracks are on interior panes of double-pane windows. The windows are set to be replaced.
A cracked pane had been discovered in September at the nearby Millennium Tower. That building, which is less than a block from the Salesforce Tower, has been beset by problems. The luxury residential building has sunk and tilted since opening. More cracked windows turned up in the troubled building - but it was later determined that those cracks were caused by some kind of external impact.
Salesforce Transit Center, which stands next to the Salesforce Tower, has had perhaps the most serious problems of any of the city's new structures. It was shut down in September, six weeks after its grand opening, when inspectors discovered cracks in two support beams under the center's public roof garden. The $2.2 billion landmark center remains closed, and a date for its reopening has not been announced.