MIAMI - A newly installed pedestrian bridge connecting the campus of Florida International University (FIU) with the city of Sweetwater west of Miami collapsed Thursday, crushing several cars on the roadway below. Florida Highway Patrol Lt. Alejandro Camacho tells CBS News there are "several fatalities" resulting from the collapse. He said the bridge was still under construction and not open to pedestrians.

In a news conference Thursday afternoon, officials said eight vehicles remained trapped under rubble at the scene, and eight people had been transported to various hospitals. City, police and fire officials declined to provide details about fatalities. Aerial footage from CBS Miami showed the vehicles stuck underneath the 174-foot, 950-ton bridge.

White House press secretary Sarah Sanders said President Trump was aware of the situation. Florida Gov. Rick Scott said he will be on the scene to meet with local officials this evening.

"Me and my boyfriend had just driven under the bridge," witness Isabella Carrasco told CBSN. "We actually commented on how new it was ... We had heard a loud bang. At first, we thought we had hit something, and when we looked around, we realized the bridge had collapsed on multiple cars. I didn't see any pedestrians walking on the bridge. When we looked around we saw that it was much, much worse."

"So many people go through this particular intersection every day, so it's very terrifying," Carrasco added.

A car trapped underneath a collapsed pedestrian bridge at Florida International University on March 15, 2018. / WFOR

Carrasco told CBSN she saw one construction worker who had sustained injuries. She said authorities pulled him to the side of the road and later transported him to a hospital by ambulance. She also witnessed paramedics performing CPR on another person at the scene. 

Witness Damany Reed told CBSN the bridge was constructed "for the safety of the students" in order for them to cross 8th Street "comfortably."

"I heard a big 'kaboom,'" Reed said. "It sounded continuous. We thought something had fallen, but it was the bridge that collapsed. It was just surreal at that moment and pretty scary."

FIU students are currently on spring break, reducing the number of pedestrians in the area. Authorities are urging the public to avoid the area of southwest 8th Street between southwest 108th Avenue and 118th Avenue indefinitely during the investigation.

n a statement, FIU said it was "shocked and saddened about the tragic events" at the bridge. The university says it is focused on rescue efforts and is "working closely" with first responders.

"Right now, the most important thing is to try and save these people who are hopefully still alive," Rep. Mario Diaz-Balart told CBS Miami shortly after the collapse. "Our thoughts and prayers are with them and the first responders who constantly risk their lives."

Munilla Construction Management (MCM) -- the company that was hired to build the bridge -- tweeted a statement in response to the collapse that reads in part: "Our family's thoughts and prayers go out to everyone affected by this terrible tragedy."

"Our deepest sympathies are with those affected by this accident," FIGG Bridge Engineers, the company hired to design the bridge, wrote in a statement. "We will fully cooperate with every appropriate authority in reviewing what happened and why. In our 40-year history, nothing like this has ever happened before. Our entire team mourns the loss of life and injuries associated with this devastating tragedy, and our prayers go out to all involved."

During a news conference Thursday, Maurice Kemp, deputy mayor of Miami-Dade County, said more than 100 firefighters are working to find victims in the rubble. 

"We have multiple fire rescue units on scene. We have our urban search and rescue technicians on the scene," Kemp said. "We have our technical rescue technicians on the scene. We also have live search dogs working a pile right now."

"All of our thoughts and prayers go to the victims of this tragedy that has occurred here today ... We thank all of the agencies that are out here supporting these efforts," added Juan Perez, director of the Miami-Dade Police Department.

Perez said the department's homicide division will take over the investigation. A reunification center has been set up at FIU. Perez said members for the public can call (305) 348-3481 for more information.

The bridge was constructed using an innovative approach called accelerated bridge construction (ABC), meant to reduce potential risks to workers, commuters and pedestrians and prevent traffic tie-ups in the area. It was moved into place on Saturday.

Construction, which cost $14.2 million, was expected to finish in early 2019. The 32-foot-wide bridge was supposed to be 289 feet long and 109 feet tall once completed. The span was the first in the world to be constructed entirely of self-cleaning concrete, which helps to reduce maintenance costs, according to a press release from the university.

The NTSB is sending a team to investigate the collapse.

Monique O. Madan of the Miami Herald captured dramatic video from the ground showing the aftermath of the deadly collapse:

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