MIAMI - Florida International University President Mark Rosenberg says his university and a neighboring community were celebrating the campus' new pedestrian bridge less than a week ago.

Authorities say the bridge was an innovative university project designed to link its campus with the nearby community of Sweetwater in South Florida. Rosenberg says: "This bridge was about goodness, not sadness. Now we're feeling immense sadness, uncontrollable sadness. And our hearts go out to all those affected, their friends and their families."Rosenberg spoke at a news conference Thursday evening with fire and law enforcement authorities and political leaders. He adds the university is committed to assisting in all efforts to overcome the tragic bridge collapse earlier Thursday.

Miami-Dade County Fire Chief Dave Downey says his crew is used high-tech listening devices, trained sniffing dogs, search cameras and other equipment in the frantic race to find any survivors still trapped in the rubble of the South Florida pedestrian bridge collapse.

Downey told a news conference Thursday evening that the work is dangerous and difficult but is continuing. He says his crews have traveled to building collapses elsewhere in the world but now are working as fast as they can.

Says Downey: "We have to remove some of this piece by piece. It's very unstable." Aerial footage at the site showed a trained dog running atop fallen concrete and sniffing in the crevices for any victims.

Sen. Marco Rubio of Florida joined first responders and Gov. Rick Scott at the briefing. He says he lamented the "tragic accident" and noted the pedestrian bridge was intended to be an innovative and "one-of-a-kind engineering designed.

He says the public and the families of the dead and injured dserve to know "what went wrong."

AP