NEW YORK - Mayor Bill de Blasio ordered all flags be lowered to half-staff across the city today in honor of police officer Dennis Guerra, who died this morning at Montefiore Medical Center.

Police Commissioner Bill Bratton says Guerra, 38, gave his life trying to save others, which is the ultimate selfless act. Guerra rushed to the 13th floor of a Coney Island building fire on Sunday trying to help those inside. He succumbed to his injuries this morning.

Commissioner Bratton presided over a special ceremony as flags were lowered at police headquarters earlier today.

Members of the Guerra family were at the ceremony at One Police Plaza.

Guerra leaves behind a wife and four children ages seven to 20.

A Coney Island teen was arrested for allegedly setting the fire that ultimately killed Guerra. Marcell Dockery, 16, allegedly told detectives that he did it because he was bored. He is charged with arson, assault and reckless endangerment. There is no word yet on if those charges will be upgraded.

Officer Guerra is the first NYPD death in the line of duty in more than two years.  The last officer to die on the job was Detective Peter Figoski, who was shot and killed after being called to the scene of a burglary in Cypress Hills in December 2011.