Saudi Arabia-funded lobbyists paid for rooms at President Donald Trump’s Washington hotel within a month of the 2016 presidential election and kept coming back, racking up more than 500 nights worth of rooms in three months, The Washington Post reported, citing documents and organizers of the stays.

The Saudi-backed organizers were putting up veterans who were offered a free trip to Washington to help lobby against a law that Saudi Arabia opposed, the Post reported.

(Read the full Washington Post story.)

The lobbyists at first were hosting veterans in northern Virginia, but switched to the Trump hotel in December 2016. One organizer said the move was because the Trump International Hotel offered a discount from the usual $768 a night rate, and denied it was to try to gain favor with Trump.

But some of the vets the Post interviewed said they felt like they were being used twice ― to lobby for Saudi Arabia, and then again to bring business to Trump.

“It made all the sense in the world, when we found out that the Saudis had paid for it,” said Navy veteran Henry Garcia. He went on three trips, and said that what made the Trump hotel trips different from trips with other veterans groups were the private rooms, open bars and free dinners.

“We’ve done hundreds of veterans events, and we’ve stayed in Holiday Inns and eaten Ritz Crackers and lemonade. And we’re staying in this hotel that costs $500 a night,” said Marine veteran Dan Cord.

Trump’s business interests are in the spotlight once again as the D.C. and Maryland attorneys general served subpoenas on the Trump Organization and a dozen related businesses on Wednesday, CNN reported.

The subpoenas are seeking business documents that may show foreign payments to the hotel.

The lawsuit alleges that Trump is profiting from foreign and state spending at his D.C. hotel, in violation of the Constitution’s ban on gifts from foreign governments. The Justice Department has signaled it may try to fight the evidence-gathering process.

Trump has defended the U.S. relationship with Saudi Arabia and Crown Prince Mohammed bin Salman, even after intelligence agencies fingered the prince in the slaying of journalist Jamal Khashoggi. The Saudi royal family and its allies have spent tens of millions on Trump hotels and condos.

The Trump Organization didn’t immediately answer HuffPost’s request for comment.