The attack happened on Thursday morning during Yom Kippur, the holiest day of the Jewish calendar. Two people have died and three others are hurt.
The suspected attacker was killed and three other suspects have been arrested.
The NYPD said that they already had heightened security and high visibility patrols in place at synagogues in New York City due to the holiday.
New Yorkers who attended Yom Kippur services in the city said they were disheartened by the terror attack.
"It seems like we just can't find any happiness in the world," said Upper East Side resident Lexa Merson said.
Marjorie Neu attended services at Central Synagogue on Lexington Avenue.
"The rabbi did address the issue of everybody's attitude and think about the future that we that are going to sow and we are not going to see the rewards," Neu said.
Mayor Eric Adams released a statement, saying the city mourns with the Jewish community both here and abroad.
"On a day when Jews around the world gather to reflect and pray for the year ahead, terrorism in the UK has stolen innocent futures and lives," Adams said.
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