The House Ethics Committee announced on Tuesday it is investigating four members: Democrat Tom Malinowski of New Jersey and Republicans Mike Kelly of Pennsylvania, Jim Hagedorn of Minnesota and Alex X. Mooney of West Virginia.

The cases were investigated by the nonpartisan Office of Congressional Ethics, which concluded that in each case there was a substantial reason to believe that a violation had occurred. The OCE is a fact-finding office and, unlike the Ethics Committee, cannot discipline members or issue subpoenas.

CQ Roll Call first reported that Mooney was under investigation by the ethics office in August. The OCE found that Mooney had spent thousands in campaign funds on personal pursuits, including on fast food and family vacations. Further, it found that he had failed to properly report over $40,000 in expenditures.

“Congressman Mooney is cooperating fully with the inquiry into this matter,” Mark Harris, a Mooney campaign spokesperson, said in an emailed statement in August.

The House Ethics Committee will make a further announcement on the matters no later than Oct. 21.

The Pittsburgh Post-Gazette reported that Kelly was pushing the Trump administration to launch an investigation into foreign steel imports. Days before the Department of Commerce announced the investigation, Kelly’s wife bought stock in Cleveland-Cliffs, a Pennsylvania steel company that was threatened by the very imports the Commerce Department was investigating, according to the Post-Gazette.

“The stock purchase, disclosed as required by U.S. House rules, created a scenario in which Mr. Kelly’s spouse, Victoria Kelly, may have gained personally from the actions of his public office, Congressional ethics experts said in interviews,” the paper reported.

Kelly’s office did not respond to a request for comment.

Business Insider had previously reported that Malinowski failed to disclose his stock trades. Members are required by the STOCK Act to report their securities transactions — exceeding $1,000 — within 45 days of the trade execution.

“The Committee’s statement extending Rep. Malinowski’s review period reflects their standard practice when handling matters from OCE,” said Colston Reid, a spokesperson for Malinowski. “Rep. Malinowski continues to participate in this routine process in good faith, and remains committed to complete transparency with the public; going beyond the requirements for Members of Congress by placing his holdings in an Ethics Committee approved qualified blind trust.”

The Minnesota Reformer has previously reported on questionable spending by Hagedorn’s office.

“Congressman Hagedorn personally self-reported this matter to the Ethics Committee last year and will continue working with it to bring it to an appropriate conclusion,” Elliot Berke, managing partner of Berke Farah LLP, said in a statement on behalf of Hagedorn. “The fact that the OCE, which provides non-binding recommendations to the Ethics Committee, decided to investigate something that was already under review was a waste of taxpayer funds and House resources.”