HOUSTON -

Police tell Local 2 the ex-boyfriend of a missing woman has confessed to her murder.

Detectives said Mark Castellano, 37, confessed to killing Michelle Warner, 31, during an argument.

Detectives said Castellano also confessed to dumping Warner's body outside the Midland/Odessa area of Texas. Castellano helped lead police to Warner's body on Sunday.

Police said it appeared Warner had a broken neck, but they are waiting on an autopsy to determine a specific cause of death.

Warner disappeared from her southwest Houston apartment along with the couple's three-year-old son on Sept. 21, sparking a massive search.

Police said it appears Castellano fled to the Midland/Odessa area after the murder to stay with family members. However, investigators said Castellano flew back to Houston on Sunday and gave a confession.

Investigators said the couple's son was found unharmed with family members in north Texas.

Police said while the pair was no longer a couple, Warner moved in with Castellano because she fell on hard economic times. But was just about to start a new job as a paralegal.

When reached Sunday by phone, Warner's brother David Chaffin told Local 2 he knew the coupled argued but "never thought something like this would happen."

Chaffin said the family had flown to Los Angeles to tape a segment for the Dr. Phil show about Warner's disappearance and found out about the confession "as soon as we hit the ground."