The FBI has launched an internal investigation into one of its own Twitter accounts over a mysterious slew of controversial tweets. The account in question, @FBIRecordsVault, which was dormant for over a year before it sprang to life only to post a series of allegedly pro-Trump tweets on 30 October, according to reports.

The account released a trove of documents, one of which detailed information on Donald Trump's father Fred Trump, who the account characterised as a "philanthropist". On 1 November, the FBI account tweeted documents relating to Bill Clinton's controversial pardon of Marc Rich. According to a report by ThinkProgress, it was this tweet that garnered major attention. At the time of writing, the tweet had received over 8,000 likes and has been retweeted over 9,000 times.

The account also released documents and aerial surveillance videos connected to the April 2015 Baltimore protests against police brutality, sparked by the death of Freddie Gray, an African American who died from spinal injuries while in police custody, a week after his arrest.

The assistant director for the FBI's Office of Professional Responsibility Candice Will said she had referred the matter to the FBI's Inspection Division for an "investigation". Will's comments were a response to a complaint made by Jonathan Hutson, a former investigative reporter, who currently works in communications in Washington, DC.

Assistant director of the FBI's Inspection Division Nancy McNamara confirmed to Hutson having received the complaint, which was also copied to Voviette Morgan, a 19-year veteran currently serving as Assistant Special Agent in Charge of the FBI's Los Angeles office.

According to TPM, following the FBI account's tweets, the FBI said in a statement: "The FBI's Records Management Division receives thousands of FOIA requests annually which are processed on a first in, first out (FIFO) basis. By law, FOIA materials that have been requested three or more times are posted electronically to the FBI's public reading room shortly after they are processed. Per the standard procedure for FOIA, these materials became available for release and were posted automatically and electronically to the FBI's public reading room in accordance with the law and established procedures."

The FBI account's mysterious tweets came on the heels of FBI director James Comey's controversial letter to Congress, revealing the agency's probe into new emails possibly linked to the previously closed investigation of Hillary Clinton's private email server. US DOJ officials, among others, have since slammed Comey for his decision in releasing the information.