CNN — A Norfolk Southern conductor was killed Tuesday after being struck by a dump truck at a facility in Ohio, prompting a National Transportation Safety Board investigation of the railway’s safety culture due to the “number and significance” of recent accidents.

The conductor, identified as 46-year-old Louis Shuster, was fatally injured early Tuesday morning at the Cleveland-Cliffs Cleveland Works property, the railroad said in a news release. It is the third incident involving the railroad in the state in just over a month.

Shuster was struck when a dump truck carrying limestone collided with the front left side of the first car of the train. He was outside the car when he was struck, a Cleveland police spokesperson told CNN.

Norfolk Southern is working with Ohio Gov. Mike DeWine, the Cleveland Police Department and Cleveland-Cliffs representatives to learn more, it said.

The National Transportation Safety Board said on Twitter that it had sent crews to the scene.

The NTSB said in a statement later that its safety culture probe encompasses multiple incidents and three deaths since December 2021, including the toxic East Palestine derailment and the employee killed earlier Tuesday. It is already investigating a October 28 derailment in Sandusky, Ohio.

“The NTSB is concerned that several organizational factors may be involved in the accidents, including safety culture,” the board said in a statement. “The NTSB will conduct an in-depth investigation into the safety practices and culture of the company. At the same time, the company should not wait to improve safety and the NTSB urges it to do so immediately.”

Norfolk Southern’s CEO is scheduled to testify before a Senate committee Thursday.

“Norfolk Southern has been in touch with the conductor’s family and will do all it can to support them and his colleagues. We are grieving the loss of a colleague today. Our hearts go out to his loved ones during this extremely difficult time,” the railroad said.

Conductor was Army veteran and father, union says

Shuster was member of the Brotherhood of Locomotive Engineers and Trainmen (BLET) and employed as a Norfolk Southern conductor, according to the union.

“Lou was a passionate and dedicated union brother,” said Pat Redmond, Local Chairman of BLET Division 607. “He was always there for his coworkers. He was very active in helping veterans who worked on the railroad and veterans all across our community.”

Shuster, a resident of Broadview Heights, Ohio, was president of BLET Division 607 in Cleveland. Shuster has a 16-year-old son and cared for his elderly parents, and was an Army veteran, the union said.

“This was a tragic situation and it’s a devastating loss for the Shuster family as well as the members of this union,” said BLET National President Eddie Hall. “All railroad accidents are avoidable. This collision underscores the need for significant improvements in rail safety for both workers and the public.”

Cleveland-Cliffs is a flat-rolled steel company, according to its website, and its Cleveland Works facility sits on the Cuyahoga River in Cleveland.

CNN has reached out to Cleveland-Cliffs, Cleveland police and the Ohio governor’s office for more information.

The conductor’s death comes as Norfolk Southern is facing criticism for two recent derailments in Ohio, including one in East Palestine last month that resulted in the release and burning of a toxic chemical that left nearby residents complaining of headaches, coughing and rashes they believe are tied to the fiery crash.

As the railroad works with the Environmental Protection Agency to remediate the site, it announced a new six-point safety plan Monday designed to help prevent similar derailments in the future.

And in Springfield, about 200 miles southwest of East Palestine, another Norfolk Southern freight train derailed Saturday.

The crash knocked out power and the area and resulted in a temporary shelter-in-place order for homes within 1,000 feet of the scene. Crews later determined nothing had spilled from the derailed cars and there was no environmental harm.

Casualties, including injuries and deaths, involving railroad employees are not uncommon, according to data from the Federal Railroad Administration, which shows there were more than 13,500 incidents involving on-duty employees across the industry in 2022, including 1,060 involving Norfolk Southern employees.

Forty-two rail employees died while on duty last year, the administration said. Five of those individuals were Norfolk Southern employees.

CNN’s Ross Levitt, Vanessa Yurkevich, Chris Isidore, Greg Wallace, Pete Muntean, Greg Wallace, Celina Tebor, Isa Kaufman-Geballeand and Kelly McCleary contributed to this report.