WASHINGTON (AP) — The Environmental Protection Agency on Tuesday barred the Associated Press, CNN and the environmental-focused news organization E&E from a national summit on harmful water contaminants.

The EPA blocked the news organizations from attending Tuesday’s Washington meeting, convened by EPA chief Scott Pruitt.

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EPA spokesman Jahan Wilcox told the barred organizations they were not invited and there was no space for them, but gave no indication of why they specifically were barred.

Pruitt told about 200 people at the meeting that dealing with the contaminants is a “national priority.”

Guards barred an AP reporter from passing through a security checkpoint inside the building. When the reporter asked to speak to an EPA public-affairs person, the security guards grabbed the reporter by the shoulders and shoved her forcibly out of the EPA building.

During the summit, Environmental Protection Agency chief Scott Pruitt said dealing with a slate of toxic chemicals contaminating some drinking water systems around the country is a national priority.

Pruitt, who drew scrutiny from lawmakers after EPA emails released this month showed that the agency had intervened in the publication of a new government study on the contaminants, convened what he called a national summit on the chemicals.

The chemicals are as perfluoroalkyl and polyfluoroalkyl. Used in some nonstick coatings, in firefighting foam and elsewhere, the chemicals can cause developmental defects and other health problems. Authorities say the contaminants are present in dangerous levels in some water systems, including several near military bases and industries.

Pruitt drew questions from Republican and Democratic lawmakers last week after emails obtained under the Freedom of Information Act revealed an unidentified White House official calling a pending federal toxicological report on the chemical a “potential public-relations nightmare.”

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The emails also revealed EPA officials intervening in the release of the study, which remains unpublished. Politico first reported on the emails.

Pruitt, formerly the Republican attorney general of Oklahoma, invited what the EPA said were 200 people to Tuesday’s Washington session on the chemicals.

The people attending represented states, tribes, the chemical industry and other sectors, along with some environmental representatives.

“It’s clear this issue is a national priority,” Pruitt said, opening the session.

He pledged to start work toward establishing a legal maximum limit for the contaminants in drinking water systems.

The EPA would reach out to communities with drinking water contaminated by the chemicals over the summer, agency officials said.

The EPA is “very focused upon action,” Pruitt said. “We want to hear from all of you as we take the next step.”

Environmental groups and some lawmakers have accused Pruitt of meeting more often with industry representatives, conservative political groups and lobbyists than with ordinary people affected by dangers that the EPA regulates.

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