Oct. 4, 2013 -- The woman who led police on a high-speed chase near the U.S. Capitol before being shot dead had a history of mental illness and believed President Obama was electronically monitoring her Connecticut home in order to broadcast her life on television, sources said.

Sources told ABC News that Connecticut police had twice in 2012 been called by Miriam Carey's boyfriend, who reported the woman was delusional, acting irrationally and putting her infant daughter in danger.

Carey, 34, a dental hygienist from Stamford, Conn., was killed by police Thursday after trying to ram a White House gate and leading cops on a chase down Pennsylvania Avenue with her 1-year-old daughter in the car. The toddler was uninjured and placed in police custody.

According to sources Carey believed she was the "prophet of Stamford" and was capable of communicating with Obama.

Her mother, Idella Carrey, told ABC News that her daughter had been hospitalized after suffering post-partum depression.

On Dec. 10, 2012, police were called to Carey's home by her boyfriend Eric Francis, 54, father of her baby. Francis told police Carey was emotionally disturbed and he believed his daughter was in danger, according to sources.

Carey told police President Obama had placed Stamford on lockdown and had arranged to have her home electronically monitored and her life broadcast on television, sources said.

Police handcuffed Carey and remanded her for a mental health evaluation. According to sources, Carey had a family history of schizophrenia and was taking medication for a mental illness.

On Dec. 21, Francis again called police to report his girlfriend was "off her medication" and acting erratically.

In January, the source said, a state social worker met with Carey and Francis and Francis told the social worker that Carey was "100 percent back to normal." Carey told the social worker she had been diagnosed with post-partum depression, was on prescription medication, and was receiving treatment, the source said.