Former State Dept. contracted diplomatic security officer arrested on Jan. 6 charges

A former State Department contracted officer responsible for diplomatic security was arrested Tuesday on charges that he breached the U.S. Capitol on Jan. 6.

Kevin Alstrup was charged with four misdemeanor offenses including entering and remaining in a restricted building, disorderly and disruptive conduct in a restricted building, disorderly conduct in a Capitol building and parading, demonstrating or picketing in a Capitol building.

Alstrup was employed as a State Department diplomatic security officer at the time of the investigation when the FBI asked his supervisor for help confirming his identity, according an FBI affidavit.

The FBI determined Alstrup "is familiar with providing security and protection for high-ranking government officials or sensitive locations, like embassies."

Alstrup is no longer employed by the State Department. An official said he had been providing uniformed officer services for the department as a third-party contractor.

In November, a former Trump administration State Department appointee was sentenced to nearly six years in prison for his role in the Jan. 6 attack on the U.S. Capitol.

Frederico "Freddie" Klein was convicted of eight felonies including six assaults, civil disorder and obstruction of an official proceeding.

Prosecutors said he "waged a relentless siege on police officers" as he attempted to enter the Capitol with a large mob of rioters.

ABC News' Shannon Crawford contributed to this report..