The Florida Republican charged the attacks were a “documented fact.”

In a series of tweets Sunday, Rubio dismissed comments by Sen. Jeff Flake of Arizona, a longtime advocate for improving ties with Cuba, stating that any U.S. official briefed on the mysterious events in Havana “knows full well that while method of attack still in question, that attacks and injuries occurred isn’t.”

“It’s a documented FACT that 24 U.S. govt officials & spouses were victims of some sort of sophisticated attack while stationed in Havana,” Rubio tweeted. Flake, a Senate Foreign Relations Committee member and a longtime leading advocate of detente with Cuba, met Friday with high-ranking Cuban officials including Foreign Minister Bruno Rodriguez and officials from the Interior Ministry, which oversees domestic security and works with foreign law-enforcement agencies. During a meeting with top Cuban officials, including Foreign Minister Bruno Rodriguez, Flake was informed that after four trips to Cuba, the FBI had found no evidence that the mysterious sickness experienced by several US diplomats was the result of foul play. After meeting with high ranking Cuban officials, Flake said classified briefings from U.S. officials had given him no reason to doubt Cuban officials who said there was no evidence any health symptoms were a result of an attack. He said that classified briefings has backed up Cuban claims that they were not behind the illnesses, which struck 24 U.S. officials and their spouses in Havana starting in 2016. US Secretary of State Rex Tillerson has said he is “convinced these were targeted attacks.” Cuba says the mysterious string of illnesses has been unjustly used to damage relations between the two countries – which were partially restored under President Barack Obama. Due to the illnesses and health risk, the U.S. withdrew most of their diplomats and officials out of Havana and did the same to Cuban diplomats in Washington.
U.S. Senator Jeff Flake tells Cuban officials there is "no evidence" of a suspected sonic attack on U.S. diplomats at the U.S. embassy in Havana.