Rubio seems to be referring to some stories about Merino which surfaced more than 8 years ago and attempted to establish links between Merino and the FARC guerrillas in Colombia after a laptop computer was captured from the FARC. From time-to-time, conservative US politicians like Rubio trot out the accusation when they want to dump on the FMLN. I am unaware of any authority having made a comprehensive investigation into the allegations surrounding Merino. The FMLN denounced the Florida senator this weekend. The party launched an ad hominem attack on the senator, calling him “a reactionary politician with Cuban roots, known for his extreme positions, anti-immigrant, and associated with the Cuban-American mafia of Miami.” I’m not sure what Rubio was up to in specifically naming Merino. Usually conservative Republicans only talk about El Salvador when El Salvador is about to have an election, in an obvious attempt to influence votes in the Central American country.