Alabama’s U.S. senators joined six of their colleagues Monday to press the Commerce Department to be firm with a Vietnamese catfish exporter accused of selling filets below market value – a practice known as dumping that harms the bottom lines of America’s catfish farmers.

Alabama is the country’s second-largest catfish producer, according to the Alabama Farmers Federation. About 6,135 pounds of catfish per acre of catfish farmland are produced a year in the state, mostly in the western part of the Black Belt.

U.S. Sens. Richard Shelby, R-Ala., and Doug Jones, D-Ala., were among eight senators who wrote to Commerce Secretary Wilbur Ross, urging a Commerce Department Agency to not cut any more slack for Vietnamese exporter Hung Vuong Group (HVG) after the Vietnamese Embassy intervened on HVG’s behalf.

Amid allegations that HVG dumped catfish filets into the U.S. market, the Commerce Department initially rejected a questionnaire sent by the company in response to the allegations because the questionnaire was incomplete and late. But the department reversed its decision after the Vietnamese Embassy stepped in, allowing HVG to resubmit the questionnaire.

“We are troubled by this series of events, as in recent years Commerce has consistently found significant dumping by Vietnamese fish fillet exporters, and has determined repeatedly that many exporters have been uncooperative in responding to the Department’s questionnaires,” the senators wrote. “The decision by Commerce to consent to a Vietnamese Embassy official’s request to allow uncooperative Vietnamese parties to impede your Department’s proceeding with further delays will have a catastrophic effect on the domestic industry. Our catfish farmers rely on strong enforcement of U.S. antidumping laws to ensure they can compete on a level playing field.”

With Commerce Department officials expected to travel soon to Vietnam to investigate the dispute, the senators told Ross to urge the officials “to conduct this verification rigorously, and not tolerate further delays or obstruction from HVG or other Vietnamese officials.”

“Vietnamese respondents or any other parties that fail to comply with requests for timely and accurate information, do not deserve more favorable treatment than U.S. catfish producers,” the senators wrote to Ross. “We hope your department will remain committed to strong implementation of U.S. antidumping laws, and that procedural rules will be applied to all parties in an impartial manner.”