The U.S. Justice Department filed a lawsuit against Norfolk Southern over the major train derailment that occurred in East Palestine, Ohio, last month.

The suit, filed Thursday on behalf of the Environmental Protection Agency, accuses Norfolk Southern Railway Company and Norfolk Southern Corporation of "unlawfully polluting" the country's waterways and violating the Clean Water Act, which prohibits groups from releasing toxic pollutants into waterways without a government permit.

The department also means to hold the company and its subsidiary accountable for the "full cost" of the environmental cleanup, seeing $120,000 for each day Norfolk Southern is found to be out of compliance.

The federal government is the latest group to sue Norfolk Southern in response to the Feb. 3 derailment. The state of Ohio, residents and several local business owners also have filed complaints related to the crash, which happened when 38 cars from a Norfolk Southern train careened off the tracks in East Palestine and ignited a dayslong fire.

At least 11 of the cars contained hazardous materials, including vinyl chloride, butyl acrylate, ethylhexyl acrylate, as well as benzene residue from past shipments. Exposure to these chemicals can lead to increased risks of cancer, fetal development issues and damage the skin, liver, kidneys, lungs and other organs.

Thousands of residents were forced to evacuate while government officials worked to prevent an uncontrolled explosion. On Feb. 6, Ohio Gov. Mike DeWine approved an operation to avoid a blast by intentionally burning the hazardous materials.

The suit says that after because of the derailment and its aftermath, a spectrum of hazardous materials entered the soil and multiple waterways in the area, including the Ohio river. Thousands of aquatic animals were killed, the complaint says, citing the Ohio Department of Natural Resources.

Norfolk Southern has paid more than $24 million in reimbursements and cleanup costs, and the company has vowed to set up funds to address long-term concerns, including health care, property values and water quality.

"Our job right now is to make progress every day cleaning up the site, assisting residents whose lives were impacted by the derailment, and investing in the future of East Palestine and the surrounding areas," Norfolk Southern spokesperson Connor Spielmaker told NPR in a statement. "We are working with urgency, at the direction of the U.S. EPA, and making daily progress. That remains our focus and we'll keep working until we make it right.

As of Wednesday, the Environmental Protection Agency said, toxic chemicals such as vinyl chloride or hydrogen chloride have not been detected since by its indoor air screening program at any point since the derailment. Contaminated soil and wastewater continue to be removed from the area and shipped off-site.