(ABC News) -- A woman killed by police today after a high-speed chase through Washington, D.C., that led to a lockdown of Capitol Hill suffered post-partum depression following the recent birth of her daughter, the suspect's mother told ABC News.
The woman was believed to be Miriam Carey, 34, a dental hygienist from Stamford, Conn., authorities told the woman's family, according to a family spokesman.
Police earlier said they were witholding the name of the driver of the car involved in the chase pending positive identification and notification of next of kin.
PHOTOS FROM THE SCENE: Computer | Mobile
Authorities said the woman led police on a chase down Pennsylvania Avenue to the Capitol after ramming a gate at the White House.
Authorities described Carey has having a "mental illness."
"She had post-partum depression after having the baby" last August, said the woman's mother, Idella Carey.
She added, "A few months later, she got sick. She was depressed. ... She was hospitalized."
Carey had a 1-year-old daughter named Erica, her mother said. Police confirmed that a 1-year-old girl was taken from the car and put in "protective custody."
READ MORE: Attempt to Ram White House Gate Ends With Female Suspect Dead
Idella Carey said her daughter had "no history of violence" and she did not know why she was in Washington, D.C. She said she believed Carey was taking the little girl to a doctor's appointment today in Connecticut.
Dr. Steven Oken, her boss of eight years, described Carey as a "non-political person" who was "always happy."
"I would never in a million years believe that she would do something like this," he said. "It's the furthest thing from anything I would think she would do, especially with her child in the car. I am floored that it would be her."
A neighbor, Erin Jackson, said she believed Carey lived in the Stamford home with the baby and the girl's father. Asked if she believed Carey suffered from a mental illness, Jackson said "absolutely."
Jackson recognized the black Infinity sedan seen on television from the incident as resembling Carey's car. She said the woman's tires recently were slashed in an incident in Connecticut.
Police, including FBI and bomb disposal units, surrounded a home in Stamford Thursday evening that authorities say is linked to the investigation, but won't give specifics. Police there said they were awaiting a search warrant from Washington, though 50 people from the apartment building already were being evacuated for the night.
Cops said Carey eluded police after they stopped her car and drew their guns. When she continued to flee, she drove "very erratically, very dangerously," said Senate Sergeant at Arms Terrance Gainer.
She ultimately rammed a police car and was shot by police without exiting the car, Gainer said. Two officers, one from the Capitol Police and one from Secret Service, were injured in the incident.
No weapons were found in the car, police said.
ABC News' Michael S. James contributed to this report.