Even before 9/11, police and prosecutors in New York were worried about the possibility of homegrown terrorism in the city. But a series of arrests in recent weeks is leading some people to look more closely at Islamic State and its role in the threat. NY1's Criminal Justice reporter Dean Meminger filed the following report.

It's something law enforcement agencies have long been worried about: New Yorkers becoming terrorists. Some experts say the rapid rise of the Islamic State has exacerbated the threat.

"I think there's no question the homegrown threat has increased since ISIS,” said John Jay College Professor Charles Strozier.

Strozier is the founding director of the school's Center on Terrorism. He says emergence of the Islamic State in Syria and Iraq in the last year has attracted some followers here in the city. 

"I mean these two women in Queens, Velentzas and Siddiqui. It’s amazing. I mean they were gathering in, you know they went to a local hardware store they were gathering materials for their pressure cooker and they were inspired,” said Strozier.

Those two women arrested in Queens last week, accused of plotting to build a bomb, brought to seven the number of people charged by federal prosecutors in Brooklyn in recent weeks with trying to join the Islamic State or carry out attacks inspired by the terror group.

Faiza Patel of the Liberty and National security Program at NYU's Brennan Center for Justice says she does not believe the homegrown terror threat is increasing.

"I think the numbers have held quite steady over the years. Obviously there is a lot more interest in these cases and the police and FBI are pursuing this very, very aggressively because of … this sort of extreme egregious violence we've seen on the side of ISIS,” Patel said.

Last year there were 25 cases of Muslim Americans associated with violent terrorism. Seven people were killed in those cases.

Strozier has this harsh reminder: "We need to recognize there will be attacks at some point, somewhere, somehow."

"I think we have a level of appropriate fear,” he continued. “We don’ need to be more afraid than we are now."

Faiza Patel also warns against that. And she says any would-be attack has a double impact on Muslims.

"We ride the subway, we send or kids to school in New York City, we want to be safe too,” said Patel.