"Rogue elements" within Cuba's government might be involved in a string of mysterious attacks on U.S. diplomats in Havana, according to a top lawmaker.

"There may be some Cuban high officials, there may be some rogue elements [responsible]," Senate Foreign Relations Chairman Bob Corker, R-Tenn., told the Washington Examiner. "Who knows? ... We know they can figure out what's happening."

Corker's combination of confusion and suspicion of the Cuban government was shared by other senators who received a briefing from the CIA and other administration experts Wednesday morning. The attacks, which have produced an array of "cognitive issues" in American diplomats, led to a withdrawal of the most U.S. diplomats from Havana and the expulsion of 15 Cuban officials from the U.S. in the last several days.

Publicly, the State Department declines to blame Cuba for the attacks. Raul Castro's regime has also denied involvement and pledged to help investigate the issue. Corker emphasized the U.S. belief that the Cuban government's "excellent intelligence services" know more than they're letting on.

"There's such an awareness of Cuba's awareness of all that happens on that island," Corker said. "They own the island. They know what's going on there."

Secretary of State Rex Tillerson's decision to expel the 15 Cuban officials drew some Democratic criticism, as one senior House lawmaker suggested a "third-party" country such as Russia might be responsible for the attacks. But the move had bipartisan support following Wednesday's briefing.

"Cuba is a very tightly controlled society with a very strong intelligence service and strong medical community," Delaware Sen. Chris Coons, a Democratic member of the Foreign Relations Committee, told the Washington Examiner. "I think the burden is on them to prove that they have no involvement in what is going on."

Coons made no effort to hide his perplexity, even after the classified briefing. "The whole thing is just weird and unsettling," he said. "It just doesn't add up."

For Corker, one thing was clear. "Let me put it this way: I don't plan on traveling down there anytime soon," he told the Washington Examiner. "Just based on what I know, both meeting privately with Tillerson and the briefing today, I have no plans to go to Cuba any time soon."