Sen. Marco Rubio (R-Fla.), the early front-runner for the GOP's 2016 presidential nomination, on Thursday targeted the front-runner for the Democratic nomination, Hillary Clinton.

During an interview on "Fox and Friends," Rubio mentioned Clinton twice while discussing the attacks in Benghazi and the security situation at the U.S. diplomatic outpost there, where four Americans were killed last September.

"That post probably shouldn't have been open, and the people in charge of that -- Secretary Clinton and the State Department -- they had a steady stream of reporting that showed how dangerous it was," Rubio said.

Rubio added: "What I think is sad is how many people are around the administration, including the former secretary of state, Secretary Clinton, knew this to be the case and allowed this to move forward anyway. You would have hoped the people would have stood up and said, 'This is wrong, the American people deserve the truth.' That didn’t happen.”

A House committee held a hearing Wednesday at which three former State Department officials criticized leadership's actions before and after the attack in Benghazi. Clinton was a regular topic of discussion, as Republicans on the committee sought to tie her to the failings that lead to the deaths of the four Americans and the response that followed.