The office said it is in the middle of the investigation but did not reveal any further details.
In remarks in an Instagram live video Sunday, Franco appeared to deflect the accusations and instead said he was focused on bettering himself.
On Monday, the 22-year-old Dominican stepped away from the Rays’ current west coast road trip due to the situation surrounding social media posts involving Franco, the Rays said.
It is not clear if the social media posts MLB is looking at are related to the probe in the Dominican Republic.
Tampa Bay and Franco mutually agreed Monday that he’ll be placed on the Restricted List, administrative leave that allows Franco to not count against the 26-man roster.
“We support any steps taken by the league to better understand the situation,” the Rays said in a statement. “Out of respect for all parties involved, we have no further comments at this time.”