US authorities have said Norfolk Southern, whose toxin-laden train derailed in an Ohio town, must pay for the clean-up or face tough penalties.

The train, which derailed in East Palestine on 3 February, was carrying vinyl chloride and other potentially hazardous substances.

Norfolk Southern is now facing multiple lawsuits filed on behalf of residents, many of whom were forced to evacuate their homes.

It has apologised for the incident.

The Environmental Protection Agency (EPA), which has the power to fine or sanction firms over environmental concerns, said Norfolk Southern would “pay for cleaning up the mess they created and for the trauma they’ve inflicted on this community”.

Speaking at a news conference in East Palestine, the head of the EPA Michael Regan said the company would have to find and clean contaminated soil and water supplies and pay back the EPA for its own cleaning efforts, provide information online for residents and take part in public meetings at the EPA’s request.

The EPA will also “review and approve” Norfolk Southern’s work plan with the input of state and local authorities.

“Full transparency is the only option,” Mr Regan said, adding that in “no way, shape or form will Norfolk Southern get off the hook”.

If Norfolk Southern failed to comply, the EPA would “immediately” carry out the work itself, charge them triple the cost of the clean-up operations and fine the firm up to an additional $70,000 (£58,000) a day.

In the aftermath of the derailment, residents of East Palestine have reported ailments including headaches and nausea, and expressed fears that local water supplies are potentially harmful despite the repeated assurances of state, local and federal officials that the water is safe. Earlier on Tuesday, the Ohio Health Department opened a health clinic for concerned residents.

Authorities in both Ohio and Pennsylvania have also suggested that further legal actions may follow.

At Tuesday’s joint news conference, Pennsylvania Governor Josh Shapiro said his office had referred criminal charges against the rail firm to the state’s top prosecutor, who must now make a decision on whether to press charges.

He was joined by Ohio Governor Mike DeWine, who said Norfolk Southern “needs to be made to pay” for any medical costs stemming from the derailment.

Mr DeWine called for changes to how railroads operate, calling it “absurd” and “fundamentally wrong” that a train carrying potentially hazardous chemicals was not required to alert local authorities when it was in transit through their area.

“That has to be changed,” he said. “We’re going to do everything we can.”

Hours before the announcement, the Ohio governor and EPA chief together drank water in an effort to show the East Palestine municipal tap water was safe.

Last week, Norfolk Southern came under intense criticism from East Palestine residents after company representatives failed to appear at a town hall meeting aimed at easing fears.

A local resident, Logan Rance, told the BBC that the EPA’s announcement would be welcome for many in East Palestine.

“Hopefully they [Norfolk Southern] will be held accountable for their actions. It’s reassuring to know the ball is rolling,” Ms Rance said. “But I can only feel so much better. The damage has already been done in my opinion.”

In a statement on Tuesday, the company said it has “been paying for the clean-up activities to date and will continue to do so”.

“We are committed to thoroughly and safely cleaning the site, and we are reimbursing residents for the disruption this has caused in their lives,” Norfolk Southern said.

On Monday the company said it had already removed at least 15,000lbs (6,800kg) of contaminated soil and excavated 1.5m gallons of contaminated water.

Former US President Donald Trump plans to visit the town on Wednesday and is expected to criticise the federal government’s response to the derailment and chemical spill.

More than two weeks after the derailment, the incident has become a politically contentious issue. Senior Republicans have cited the response to the derailment as evidence that the federal government is neglecting domestic issues.

Earlier this week, East Palestine Mayor Trent Conaway told Fox News that US President Joe Biden had given a “slap in the face” to the town by travelling to Ukraine rather than Ohio.

“That tells you right now, he doesn’t care about us,” he said.

In a series of tweets on Tuesday, Mr Biden said his administration had deployed resources to East Palestine and was “on the ground hours after the train derailed” to help with their response.

He said he agreed Norfolk Southern should be responsible for the clean-up.

“This is common sense. This is their mess. They should clean it up,” Mr Biden said.

Criticism has also been directed at US Transportation Security Pete Buttigieg for not addressing the train derailment sooner.

On Tuesday, Mr Buttigieg acknowledged to the BBC’s US news partner CBS that he “could have spoken sooner about how strongly I felt about this incident, and that’s a lesson learned for me”.