Transportation Secretary Pete Buttigieg traveled to East Palestine, Ohio, on Thursday to visit the site of the train derailment that spilled toxic chemicals into the environment.
At the site, Buttigieg was briefed by the Transportation Department's on-scene personnel. Later, he will meet with emergency responders and members of the community in East Palestine and receive an update from the National Transportation Safety Board's (NTSB) investigation into the accident.
The Transportation Secretary's visit coincides with the release of the NTSB's preliminary report, which will contain factual findings from the investigation into the Norfolk Southern derailment.
About 50 rail cars, including 10 carrying toxic chemicals, derailed on the evening of Feb. 3 in East Palestine, a small town on the Ohio-Pennsylvania border.
Officials conducted a controlled release of vinyl chloride from some of the cars three days later to avoid an explosion, sending hydrogen chloride and phosgene into the air.
Buttigieg, who waited for days before making public comments about the accident, vowed to "hold Norfolk Southern accountable" in a letter sent to the company's CEO Alan Shaw on Sunday.
"This is the right time for Norfolk Southern to take a leadership position within the rail industry, shifting to a posture that focuses on supporting, not thwarting, efforts to raise the standard of U.S. rail safety regulation," Buttigieg wrote in the letter.
"It is imperative that your company be unambiguous and forthright in its commitment to take care of the residents — now and in the future."
Fox News' Paul Best contributed to this report.