A teenager has appeared in court in connection with attacks on synagogues in New Jersey.

Anthony Graziano pleaded not guilty at an initial hearing on Wednesday, after being charged with firebombing two synagogues.

The charges against him include nine counts of first degree attempted murder, third degree arson and bias intimidation. The attacks occurred earlier this month, on January 3 and 11.

The second incident, which saw Molotov cocktails and other incendiary devices thrown into the building, left the congregation's rabbi with injuries.

"Our community breathes easier now that law enforcement has identified and arrested this individual who allegedly was deeply infected with antisemitism," said Etzion Neuer, a regional director of the Anti-Defamation League.

"It is disturbing that an alleged hatemonger like Graziano was living in our midst. His arrest sends a clear message that violent criminal actions targeting the safety of any group of individuals will not be tolerated in our community."

The suspect's father told CBS news that he did not believe his son hated Jewish people.