Faisal
Shahzad, 30, was arrested Monday night in connection with a car bomb
parked in New York's Times Square.

(CNN) -- The suspect in the failed Times Square car bombing
is a Pakistani who became a naturalized U.S. citizen in April 2009 and
had not been on national security radar.

Faisal Shahzad, 30, of
Bridgeport, Connecticut, was arrested Monday night at John F. Kennedy
International Airport in New York as his flight to Dubai was about to
take off, law enforcement officials said.

Shahzad had traveled
to Dubai before. He took a flight there in June 2009 and stayed out of
the United States until his return on Feb. 3, officials said.

A
woman who said she had lived next door to Shahzad in Shelton,
Connecticut, told CNN on Tuesday that the man she knew didn't say much
and claimed to work on Wall Street in New York.

"He was quiet. He
would wear all black and jog at night. He said he didn't like the
sunlight," Brenda Thurman said.

She said Shahzad, his wife and
two children and his wife's two sisters lived next to her for about
three years, moving out in July 2009. People whom she believes were
plainclothes law enforcement officers appeared to be staking out the
house Monday, Thurman told CNN affiliate WTNH-TV.

The neighbor said she often saw Shahzad
leaving the home in the morning and returning in the evening. She also
saw him in his yard with his children, a boy and a girl, and the family
usually wore traditional Muslim attire, she told WTNH-TV.

She
said she never suspected he might be involved in a possible terror
attack.

"I didn't think he was capable of doing something like
that. ... I'm very shocked," she said.

Thurman said her daughter
often played with Shahzad's daughter, but she herself didn't have much
contact with the family.

Shahzad's wife spoke English, but was
apparently so insecure about her language ability that she told people
she did not, Thurman said.

"I never knew she spoke English until
it was time for her to move," Thurman said.

Shahzad's wife told
Thurman in July 2009 that the family was moving to Missouri. A few weeks
after they left their home, the lender foreclosed on the property and
changed the locks, the neighbor said.

Shahzad had made
international calls in recent weeks, but said he acted alone in the
attempted bombing, investigators said.

Cell phone calls
conducted for the purchase of the vehicle used in Saturday's bombing
attempt helped lead police to the suspect, law enforcement sources said.

Sources said investigators got cell phone information from the
daughter of the Nissan Pathfinder owner. She sold the vehicle to Shahzad
on behalf of her father.

She had been talking on the phone to
Shahzad in arranging the purchase of the SUV, which was advertised for
sale on Craigslist.

The Nissan Pathfinder was parked in Times
Square containing propane tanks, fertilizer and gasoline on Saturday
night. After police retrieved the vehicle identification number of the
Pathfinder, they located the registered owner of the vehicle.

The
sources said the owner's daughter had met with Shahzad at a Stratford,
Connecticut, grocery store, for the sale. Shahzad took the car for a
test drive in the parking lot and bought the vehicle for $1,800 in cash.

Bridgeport, where Shahzad resides, is a
working class city of 130,000 on Long Island Sound, 66 miles northeast
of New York City. Per capita income there is 26 percent below the
national average, and 27 percent of its residents are foreign-born, more
than twice the national average, according to the U.S. Census Bureau.