DALLAS (CBSDFW.COM) – Police say a man shot his common-law wife six times in her back before barricading himself in their apartment with their two young children, triggering a two-hour standoff with Dallas SWAT officers in the 5800 block of Bernal Sunday evening.

The woman survived the attack and was able to make it to her mother's apartment in the same complex. While they called police, the suspect's brother in law said the suspect called his family to confess.

"He called us on the telephone, saying he had killed his woman," Dora Cerrano said in Spanish.

Police have not identified the victim or the suspect.

Police say the man turned himself in just after 6:30 p.m. Saturday. The twin boys, age four, were unharmed and are now with family members. The victim has been transported to an area hospital. Her condition is not known.

Cerrano said the family was at a loss as to what would drive Martinez to do this.

"I don't know, they had problems, I think," she said. "We don't know."

The victims' brother said his mother was aware the couple was having problems and warned her daughter about the man.

Police have charged the man with assault with a deadly weapon.