HARTFORD, Conn. -- An internal investigation ended with the arrest of a Hartford police officer, according to the department.

The investigation was launched based on a complaint by Hartford Mayor Eddie Perez's nephew.

The Hartford Police Department Internal Affairs Division executed a warrant for the arrest of Officer Matthew Secore on Tuesday.

Secore was charged with assault in the third degree -- a misdemeanor. He was released on a written promise to appear in court on May 18.

Secore is the brother of a tow-truck driver who was beaten while performing a routine tow at a housing complex on Wethersfield Avenue.

Perez's nephew, Ruben Perez, 21, was charged in connection with driver Slade Secore's beating.

Perez's complaint against Officer Secore stemmed from injuries Perez received while in a holding cell in connection with the alleged beating of Matthew Secore's brother.

Police had launched an internal affairs investigation into Secore, who they said was off-duty Sunday when police said he allegedly went to the jail and visited Perez.

Hartford police said Officer Secore was transferred to an administrative assignment pending the conclusion of an internal disciplinary investigation.

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