If you've been to the Chattanooga Riverfront lately, you've probably seen the damage. Six square panels on the glass walking bridge are cracked and shattered. Now three weeks since the damage was discovered, officials still don't know why. City parks director tells NewsChannel 9 the damage was likely done by vandals, but surveillance cameras focused on the bridge caught no one in the act. Brady says the bridge is safe, despite the cones and caution tape surrounding the glass panels. The city is investigating whether it can replace the panels with stronger glass that's harder to break. Brady explains there are three levels of glass on the bridge. He says only the top layers, the thinnest of all three, are broken. As for more security, city council will decide Tuesday night whether to buy more surveillance cameras for along the Riverfront. The city is willing to spend up to $600,000 on the equipment.