CHICAGO (AP) _ A boy at the center of a four-year custody battle was taken sobbing from his adoptive parents Sunday by the mother who had given him up and the father he has never met.

Biological parents Otakar Kirchner and his wife picked up the boy known as Baby Richard at the adoptive parents' suburban home in the late afternoon.

Kirchner demanded Friday that the adoptive parents turn the 4-year-old boy over to him within two days.

The Illinois Supreme Court granted Kirchner custody in January. Kirchner said he wanted a gradual transfer of custody to make it easier on the child, but talks broke down with the adoptive parents, known in court papers as Jane and John Doe.

The Kirchners decided to take custody immediately, ``despite our every effort and the Does' willingness to make this change in custody in a way that would not destroy this child,'' said Laura A. Kaster, who represents the adoptive parents.

Kirchner was estranged from the boy's mother when he was born in March 1991. She put the baby up for adoption, and Kirchner was led to believe the child was dead. When he learned the truth, he began pursuing custody. He and the boy's mother are now married.

The U.S. Supreme Court twice refused to consider the Does' case. A third motion was filed with the court last month.