Miami (AFP) - Miami police said Wednesday they arrested a 15-year-old boy over the murder last year of a rabbi that shocked the Jewish community in the United States.

Rabbi Joseph Raksin, 60, from New York, was shot dead during a robbery in August 2014 as he made his way to a synagogue in the Florida city.

"Today I am here to announce that yesterday this fine team of lawyers went to the grand jury and indicted 15-year-old DeAndre Charles as the gunman in this cold-blooded murder," Miami-Dade state attorney Katherine Fernandez Rundle told reporters.

Charles, who was just 14 at the time of the robbery, faces charges of first-degree murder and will be tried as an adult.

"We will not rest until the other perpetrators are arrested," Acting Miami-Dade police director Juan Perez vowed.

Raksin's daughter Shuli Labkowski said his killing had left the family bereft.

"His murder at the hands of thugs has caused an emptiness and a void that cannot be replaced," she said.

"He was a good, kind and caring father and a wonderful individual whose life was cut short by a violent act while visiting his family and grandchildren."