Editor’s note: This story has been updated with a comment from HII’s Newport News Shipbuilding.

Lawmakers demanded answers from the U.S. Navy on Friday following news reports that defective welds may have been knowingly applied to U.S. submarines and aircraft carriers under construction at Newport News Shipbuilding in Virginia.

The revelations were first reported by US Naval Institute News.

Few details about the case were made public Friday, including the potential risks to sailors serving aboard the affected ships and whether those ships would become unavailable for operations because of poor welds.

In a statement late Friday, HII, the company that owns the shipyard, said it had “discovered through internal reporting that some welders were knowingly circumventing certain welding procedures.”

“Based on our initial investigation, there is no evidence of malicious intent,” the company said. “When we discovered this, we took action to communicate with our customers and regulators, investigate, determine root causes, diagnose the problem and take immediate corrective action while we work on longer-term solutions. ”

The company’s statement did not provide further information on corrective actions or longer-term solutions.

Earlier Friday, the Republican and Democratic heads of the House of Representatives Armed Services Committee issued a joint statement calling reports of the defective welds “very concerning.”

“The Department of Defense must immediately provide our committee with answers and a plan for how they will protect U.S. Navy ships from tampering,” said the statement from committee chairman Rep. Mike Rogers, R-Ala., and ranking member Rep. Adam Smith , D-Wash., States. “Absolute transparency with Congress is essential.”

The ranking member of the committee’s Seapower and Projection Forces Subcommittee said in a statement that members were “already in close contact with Navy leadership to determine the extent and severity of the weld quality problem.”

“Every time there is a welding defect on Navy ships and submarines, the safety of the crews serving aboard is jeopardized and the availability of these platforms is hampered,” said subcommittee representative Rep. Joe Courtney, D-Conn., . “It is imperative that Navy leadership makes its investigation public in a timely manner in the coming weeks.”

The Navy said Friday that it was “aware of the issue and a thorough review is underway to determine the scope.”

“The safety of our sailors and our ships is of the utmost importance,” the maritime service said. “We are working closely with industry partners to address this situation and will provide additional information as it becomes available.”

The Newport News yard is one of two yards in the United States that focuses on the nuclear fleet.

The yard builds parts of several submarine classes, as well as Ford-class aircraft carriers.

HII did not immediately respond to a request for comment from Military Times, but USNI News reported that the company had reported the matter to the U.S. Department of Justice.