Eli Ramos Jr. is charged with obstruction or retaliation.
He's now jailed on a $750-thousand bond.
According to an arrest affidavit, Ramos and another man, Joseph Torres, who was already arrested in this incident, saw the off-duty officer walking into the CVS Pharmacy on Southwest Parkway.
One of the men told the officer they were going to blow his head off, then reached into their coat.
The officer fled to his vehicle and the two men took off in a car.
The car was soon located and police say the driver, identified as Torres, was arrested.
Torres told officers that Ramos jumped out of the car during the pursuit.
Police say they were able to identify Ramos as the man who made the threat.