The city’s murder-free week came to an end Monday night when an 18-year-old man was shot dead in Brooklyn, authorities said.

The teen was found lying dead around 10 p.m. along 53rd Street and Avenue J in Flatlands by a passing livery cab driver who threw him in his car and brought him to Kings County Hospital where he was pronounced dead, cops said.

It was the first homicide in just over a week, when 49-year-old Emmanuel Capers was found shot to death in a car in Crown Heights Oct. 6, according to police.

NYPD stats show that there have been 256 murders so far this year, a 26 percent decrease when compared with this time last year.

Of those 256 murders, 148 have been committed with firearms, cops said — a 28.8 percent decrease when compared with the number gun related homicides at this time last year.