When Environmental Protection Agency Administrator Michael Regan came to East Palestine, Ohio, on Thursday, he was the first top Biden administration official on the scene since Norfolk Southern rail cars filled with toxic chemicals derailed near the town two weeks ago.
The incident has since sparked intense health and environmental concerns that forced hundreds to flee their homes.
His visit came amid daily headline news coverage depicting angry residents and Republican and Democratic criticism of the federal government's response that has the White House on the defensive.
The day before Regan arrived, the town's mayor told ABC News he was ill-equipped to handle such a large-scale catastrophe.
"I need help," East Palestine Mayor Trent Conaway said at a town hall on Wednesday night. "I'm not ready for this. I wasn't built for this."
And Transportation Secretary Pete Buttigieg -- a favorite GOP target, who heads the agency that regulates railways -- has been singled out by not only East Palestine residents, but also by conservative news outlets and on social media.
"What happened in East Palestine is unacceptable," Sen. Ted Cruz, R-Texas, said on Fox News this week before blasting Buttigieg -- just one of many critics saying he waited 10 days before addressing the disaster on Twitter.
"And I gotta say, Secretary Buttigieg has been nowhere to be found on this issue," Cruz continued. "You know, it really is a remarkable thing that he hasn't gone to East Palestine to see what happened there. He hasn't come to Congress to explain what happened … I know he's got aspirations, but he actually has a day job -- he has a job he's been appointed to do that is incredibly important. And we need serious leadership."
Florida Republican Sen. Marco Rubio has written to President Joe Biden, calling on Buttigieg to resign.
Criticism has also come from the political left.
Democratic Reps. Rashida Tlaib of Michigan and Ilhan Omar of Minnesota called directly on Buttigieg to "address the tragedy" and ensure it "never happens again."
And West Virginia Democratic Sen. Joe Manchin, whose state borders Ohio, on Thursday called the delay in a top-level administration response "unacceptable."
“While I am glad EPA Administrator Regan will visit the site today, it is unacceptable that it took nearly two weeks for a senior Administration official to show up. I urge President Biden, Administrator Regan, and Transportation Secretary Buttigieg to provide a complete picture of the damage and a comprehensive plan to ensure the community is supported in the weeks, months and years to come, and this sort of accident never happens again," he said in a statement.
During a town hall Wednesday night, when a local resident asked Conaway, "Where's Pete Buttigieg? Where's he at?" the mayor answered, "I don't know -- your guess is as good as [mine]. Yesterday was the first day I heard anything from the White House."
At his East Palestine news conference on Thursday, Regan defended the federal response, saying the Biden administration had put boots on the ground since "day one" to do testing and promising that Norfolk Southern would be held accountable.
"Let me be clear," Regan said, "EPA will exercise our oversight and our enforcement authority under the law to be sure we are getting the results that the community deserves." He asked for the community's trust and said federal help would be available "as long as it takes."
A Transportation Department spokesperson told ABC News that "within hours of the derailment," DOT staff were on the scene to support the National Transportation Safety Board's investigation into the cause.
The department's role is to support the NTSB -- the independent agency that will issue preliminary findings and eventually, a final report -- Buttigieg has said, calling also for a reduction of "constraints on the USDOT in this area," while asking Congress to work with him on safety improvements.
"The residents of East Palestine deserve accurate information and it's unfortunate to see certain media outlets trying to cause misplaced outrage in an ongoing and serious investigation," a DOT spokesperson said in a statement to ABC News, noting that Buttigieg has spoken with both Ohio GOP Gov. Mike DeWine and Pennsylvania Democratic Gov. Josh Shapiro about the agency's support.
"When the investigation is finished, Secretary Buttigieg asked about joining the governors in East Palestine to collaborate on steps to improve rail safety and hold Norfolk Southern accountable," the spokesperson said, noting that the Transportation Department will likely become more involved in the process when discussions of future regulatory improvements begin.
The White House on Thursday expressed "absolute confidence" in Buttigieg.
"I can answer that very quickly and very, with confidence from here that we do have absolute confidence in Mayor Pete -- in secretary -- I always say that -- Secretary Buttigieg," press secretary Karine Jean-Pierre said.
Regan, the DOT spokesperson said, is the correct administration representative in the situation. While no injuries were reported from the crash, chemicals in the rail cars, including hazardous materials and vinyl chloride that was burned off in the area last week prompting a temporary evacuation, created outsize environmental and health-related concerns.
On Thursday, DeWine, for the first time, requested federal assistance during a conversation with White House officials, according to his office. Just two days before, the second-term Republican told reporters that he had earlier been contacted by President Joe Biden with offers of assistance, but he declined.
Ohio Democratic Sen. Sherrod Brown, appearing with Regan Thursday, said, "Tell me what they need from the Senate and from the House. And from the federal government. I've been working with the White House -- I spoke to the new chief of staff to President Biden just yesterday about his policy and it was literally the top of his agenda and my agenda when we spoke on five, six different things."
On Friday, in response to DeWine’s request, the Department of Health and Human Services and the Centers for Disease Control and Prevention were deploying teams of medical personnel and toxicologists to conduct public health testing and assessments in East Palestine.
Officials said the administration had secured Norfolk Southern's commitment to cover clean-up costs.
"We are committed to supporting the people of Palestine every step of the way and we are going to be on the ground helping them as long as it's needed," Jean-Pierre said at Friday's White House briefing.
ABC News' Justin Gomez and Noah Minnie contributed to this report.