The US has dropped charges against 11 of the 15 bodyguards for Turkish President Recep Tayyip Erdogan who were indicted after a brawl with protesters outside the country's embassy in Washington last May, a spokesperson for the US Attorney in DC told CNN on Thursday.

Motions to dismiss the charges against seven of the security officers were filed on February 14 -- just one day before President Donald Trump's now former Secretary of State Rex Tillerson traveled to Ankara to meet with Erdogan.

"The decisions were made after further review of evidence in the case that raised questions about the identification of individuals," a source familiar told CNN.

The source said they are not aware of any political pressure having an impact on the decisions to dismiss charges as they were based on evidentiary review that continued during the case.