NEW YORK (AP) - Two women accused in New York City's latest homegrown terrorism case may be part of what some experts say is an evolving threat - a greater willingness by women to shed blood in the name of militant Islamic jihad.

The pair allegedly wanted to "make history" on their own by building a bomb and attacking a domestic target. Just a day after the New York pair was arrested, a Philadelphia woman was accused of expressing her willingness to die as a martyr for the Islamic State group.

While past cases often involved women answering the call by the Islamic State group on social media to join the cause as nurses or wives, "the idea that they want to fight is more a noticeable new trend," said Karen Greenberg, director of Fordham Law School's Center on National Security.

The sometimes boastful and profane language one of the New York women was quoted as using in the criminal complaint - "Why can't we be some real bad b-----s?" - bolstered the idea that the defendants weren't candidates for nonmilitary roles in a caliphate.

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5 PHOTOS People accused of trying to join ISIS/recruited by ISIS See Gallery Terror cases allege women wanted to fight, not wed fighters ANKARA, TURKEY - MARCH 17: A passport photo alleged to belong to 22-years-old British woman Jalila Henry and to have been used by her twin sister Jamila Henry (known and named by Turkish officials as Jaila Nadra H) as she tried to travel through Turkey to Syria to join Daesh (Islamic State of Iraq and Levant) terrorists. Jaila Nadra H was detained after an operation staged by the Turkey's Ankara Province Police Anti-terrorism department in the city's bus terminal in Ankara, Turkey on March 17, 2015. (Photo by Turkish National Police/Anadolu Agency/Getty Images) Renu Begum, eldest sister of Shamima Begum, 15, holds her sister's photo as she is interviewed by the media at New Scotland Yard, as the relatives of three missing schoolgirls believed to have fled to Syria to join Islamic State have pleaded for them to return home, on February 22, 2015 in London, England. Police are urgently trying to trace Shamima Begum, 15, Kadiza Sultana, 16, and 15-year-old Amira Abase after they flew to Istanbul in Turkey from Gatwick Airport on Tuesday. (Photo by Laura Lean - WPA Pool/Getty Images) ANKARA, TURKEY - MARCH 17: A 22-years-old British woman, Jamila Henry (known and named by Turkish officials as Jaila Nadra H) who is alleged to have tried to travel through Turkey to Syria to join Daesh (Islamic State of Iraq and Levant) terrorists, who has been detained after an operation staged by the Turkey's Ankara Province Police Anti-terrorism department in the city's bus terminal in Ankara, Turkey on March 17, 2015. (Photo by Turkish National Police/Anadolu Agency/Getty Images) Handout still taken from CCTV issued by the Metropolitan Police of (left to right) 15-year-old Amira Abase, Kadiza Sultana,16 and Shamima Begum,15 at Gatwick airport, before they caught their flight to Turkey. Metropolitan Police officers are in Turkey as the search continues for three missing schoolgirls believed to have fled to Syria to join Islamic State. Fighters from the Iraqi Imam Ali Brigade, take part in a training exercise in Iraq's central city of Najaf on March 7, 2015, ahead of joining the military operation in the city of Tikrit. Some 30,000 Iraqi security forces members and allied fighters launched an operation to retake Tikrit at the beginning of March, the largest of its kind since Islamic State (IS) group forces overran swathes of territory last June. AFP PHOTO / HAIDAR HAMDANI (Photo credit should read HAIDAR HAMDANI/AFP/Getty Images) Up Next See Gallery Discover More Like This HIDE CAPTION SHOW CAPTION of SEE ALL BACK TO SLIDE

The two U.S. citizens "were determined to play an essentially military role, so that's different," said Jessica Stern, who was on the National Security Council staff during the Clinton administration and lectures on terrorism at Harvard University. "In that way, they were typical Americans. They're sort of between these two cultures with a kind of amorphous identity."

Another expert, Mia Bloom, professor at University of Massachusetts and the author of "Bombshell: Women and Terrorism," disagreed with the conclusion that more women are now participating in global terrorism, citing large percentages of women among insurgents in Chechnya and Turkey. In Nigeria, the Islamic extremist group Boko Haram has begun using teenage girls and young women for suicide bombings in marketplaces, bus stations and other busy areas.

Bloom also said the evidence shows the American women charged this week were probably aligned more with al-Qaida than with the Islamic State group, and that the threat was overblown.

"These are wannabe jihads that sort of have this, at least in their head, projection of importance of significance," she said. "They want to build a bomb but they don't know how to do it."

Noelle Velentzas and Asia Siddiqui were arrested at their Queens homes early Thursday following a sting operation using an undercover officer. Officers searching the homes recovered items including three gas tanks, a pressure cooker, handwritten notes on the recipes for bomb making and jihadist literature, court papers say.

Velentzas had been "obsessed with pressure cookers since the Boston Marathon attacks in 2013," and was caught on recordings saying she and Siddiqui were "citizens of the Islamic State," also known as ISIS, the papers say.

The complaint suggests the women were initially radicalized by al-Qaida literature. But it also refers to them watching a video of "in which pro-ISIS French foreign fighters urged others to leave their countries to try to fight with ISIS," and looked at a photo of "ISIS blowing up a gas pipe between Egypt and Israel."

Authorities said Friday that Valentzas, 27, was believed to have been born in Florida of Greek ethnicity and claimed to have worked as a home health aide. Siddiqui, 31, was born in Saudi Arabia and was unemployed.

Siddiqui's lawyer, Thomas F.X. Dunn, declined to talk about the allegations on Friday, saying only that he plans to "mount a vigorous defense." In a statement, Velentzas' lawyer called his client "a loving mother and wife who is innocent of the sensationalistic charges manufactured by the U.S. government."

The complaint does not identify the undercover officer or say how the officer managed to befriend the pair. But one passage gives clues about the officer's assumed role by quoting Velentzas as referring to the officer as a Muslim who, if caught, would be labeled as "an inconspicuous student studying about detonators" and "a Muslim with two terroristic friends."

Authorities declined to confirm whether the undercover officer was a woman. Past cases have relied on male New York Police Department recruits - typically with Muslim or Arab backgrounds - who agreed to skip the police academy and enter a NYPD counterterrorism program that grooms and deploys young undercover officers to expose potential plots.

In the Philadelphia case, Keonna Thomas was arrested Friday and held without bail on charges she attempted to travel overseas to join the Islamic State group before she could use an airline ticket she bought Tuesday to fly overseas. Her lawyer declined to comment.

Thomas, 30, was accused of corresponding with an Islamic State fighter who asked if she would join a martyrdom operation. She responded by writing, "that would be amazing," court papers said.

"A girl can only wish."



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