HOUSTON -

The trial of a Houston mother accused of burying her baby alive began Wednesday. Narjes Modarresi, 32, faces life without parole if she's convicted of capital murder.

According to prosecutors, Modarresi went for a walk with her son in his stroller near her apartment in the 7900 block of Westheimer on April 21, 2010. A neighbor, Rebecca Pyke, testified Wednesday that she called 911 after Modarresi knocked excitedly at a friend's door and told the women that her son had been abducted.

The 911 recording was played for jurors in court Wednesday. In it, Modarresi can be heard telling Pyke that two black men had walked up to her on the street and taken the child from his stroller, then driven off in a beige Chevy.

But the story fell apart under police questioning and Modarresi led HPD detectives to the child's body. Police determined the little boy was buried alive and died from suffocation. Prosecutor Sunny Mitchell told jurors in opening arguments that Modarresi's motive was selfishness.

"She did it because Masih was in her way. Masih was keeping her from living the life that she wanted to live. She never wanted him to begin with, she never cared for him, and he was keeping her from doing what she wanted to do," Mitchell said.

Modarresi had given birth to another son four years early after she and her husband were joined in an arranged marriage in Iran. Her attorney, George Parnham, said her mental condition deteriorated after the birth of their second child, causing her to be hospitalized at Ben Taub hospital for four weeks.

He said Modarresi was diagnosed with severe bi-polar disorder at age 17, and had attempted suicide twice. Parnham said she had become depressed, suicidal and manic.

"She constantly tells the Mental Health Mental Retardation Association people, 'I can't tend to my child,'" Parnham said. "There is no connection, there is no bonding. It is atypical of postpartum depression."

Parnham said four days before the murder her doctor had increased her anti-psychotic medication.

Parnham said her doctor will testify that, "But for the severe mental illness suffered by Narjes, this tragedy would not have occurred."

The defense is trying to convince jurors to find Modarresi guilty of the lesser charge of murder which offers the possibility of a lighter sentence.