NEW YORK The suspects have pedigrees you would expect from children of New York's elite.
Morgan Gliedman was raised on Park Avenue and reportedly went to the prestigious Dalton School, NYU and the Art Institute of Chicago.
Her boyfriend, Aaron Greene, claims to have gone to Harvard. Both are now in custody.
When Gliedman and Greene were arrested inside their apartment on Saturday, police found a container of the powerful explosive HMTD in their living room, forcing the evacuation of their neighbors, reports CBS News correspondent Seth Doane.
HMTD was the same explosive believed to have been used during the 2005 London bombings.
"It's extremely potent," said Mitch Silber, executive managing director of K2 Intelligence. "One of the reasons why it is so appealing for terrorists to use (is) because they can get all the ingredients for this at local hardware stores."
Gliedman, 27, is the daughter of a prominent real estate agent and a top-rated New York oncologist. She was also nine months pregnant at the time of her arrest. She gave birth to a baby girl soon afterwards.
CBS News has learned that police seized two shotguns, a flare launcher, nine high-capacity rifle magazines, various handwritten notebooks containing formulas, literature on how to make booby traps and homemade weapons, and pages from a do-it-yourself manual called "The Terrorist Encyclopedia."
"The assumption was that the vast majority of people there were peaceful protestors but there was a more radical fringe element to the group and there was a concern that at some point they might turn to violence if they weren't accomplishing their political aims," Silber said.
The arrests are reminiscent of other children of privilege whose lives somehow went awry. Who could forget the pictures of newspaper heiress Patty Hearst joining her kidnappers in a 1974 bank robbery?
And in 1970, just two blocks from where Gliedman and Greene were arrested, a bomb being assembled by members of the radical group the Weather Underground exploded, killing three people and destroying the brownstone where they were staying.
Gliedman and Greene have prior drug arrests. Now each has been charged with two counts of criminal possession of a weapon.
Greene is due back in court on Friday. Gliedman, who couldn't be arraigned this week while she was in labor, will make her first appearance next week.