A construction worker at the Wilshire Grand Center tower in downtown Los Angeles died Thursday afternoon after falling from the 53rd floor of the building that, when completed, will be the tallest building west of the Mississippi River.

Los Angeles Times photographer Mel Melcon was on assignment inside the 73-story-tall building when the man fell around 12:08 p.m. Thursday, the newspaper reported. The man fell onto the rear part of a car traveling on Wilshire Boulevard below, and was pronounced dead at the scene. The man’s name was not immediately released.

“It sounded like a bag of cement fell off the edge of the building,” Melcon told the Times.

The woman driving the car was reportedly uninjured.

The owner of Turner Construction Co., one of the firms overseeing the project, told KTLA5 that the worker who died was on his second day on the job as an electrician. The man reportedly worked for Irvine-based ASSI Security.

“We were deeply saddened to learn that we have lost a member of the team building the Wilshire Grand Center,” Turner Construction said in a statement. “Our thoughts and prayers are with the worker’s family. On any given day, there are 1,000 men and women working on this project. The entire team working on this project is committed to the safety of all of our workers, and we will do everything we can to understand what happened here today and prevent it from happening again.”

According to the Times, the man had been working on the 53rd floor, which does not yet have windows installed but does have an 8-foot high barrier around its perimeter that is meant to keep workers and materials from falling off of the building.

The Wilshire Grand Center will be the tallest building on the West Coast when it opens in March 2017. The structure will house a 900-room InterContinental hotel, commercial office space and retail space. It will also boast a “sky lobby” near its penthouse, where guests will be able to take in a 360-degree view of Los Angeles.

Korean Air and its parent company Hanjin Group have reportedly spent about $1 billion developing the project.