"You're going to get those leakers, Mr. President?" a reporter shouted to Trump during a pool spray as he met with members of Congress.
"Yep, we're going to find the leakers. We're going to find the leakers," Trump said. "They're going to pay a big price for leaking."
Trump complained about "low-life leakers" in his latest string of morning tweets posted earlier Thursday.
"Leaking, and even illegal classified leaking, has been a big problem in Washington for years," he posted. "They will be caught!"
In recent days, Trump's White House has been rattled by a number of reports based on information from anonymous sources.
Former National Security Adviser Michael Flynn resigned on Monday, days after reports revealed that he spoke about sanctions in a call with Russia's ambassador to the United States before Trump was sworn in.
The reports contradicted members of Trump's administration, including Vice President Mike Pence, who previously defended Flynn and denied that he and the Russian ambassador discussed sanctions on their call.
The New York Times and CNN reported on Tuesday, citing U.S. officials, that members of Trump's campaign staff made repeated contact with Russian officials before the 2016 election.
During a joint press conference with Israeli Prime Minister Benjamin Netanyahu on Wednesday, Trump called the leaks "a criminal action" and apparently blamed them for Flynn's resignation.
"I think that it is very, very unfair what's happened to General Flynn, the way he was treated and the documents and papers that were illegally, I stress that, illegally leaked," he said.