SAN DIEGO -- A statewide search to find a man police believe is responsible for a murder and the kidnapping of a child may have crossed into Mexico.

“It becomes more complicated if it involves another country,” said San Diego Police Department Lt. Kevin Rooney.

An Amber Alert was in effect Monday for a 19-month-old girl who may have been abducted from her Linda Vista home by a man suspected of fatally stabbing her mother.

Police are looking for Alejandra Gomez, who is believed to be with Gildardo Rosas Rodriguez, 31, who also goes by the first names of Gildardo or Fernando.

Rodriguez is suspected of killing Alejandra's 23-year-old mother, who was found stabbed to death at 2295 Ulric St. about 8:30 a.m. Sunday, said SDPD Lt. Jeff Sferra.

"In the morning, the people who owned the home the woman lived in -- she rented a room in the home -- checked the room that the victim was staying in and they found her stabbed to death," said Rooney.

The dead woman's name was being withheld.

“It is awful and frustrating,” said Julie Boyle, the property manager of the home where the victim was staying.

Police questioned Boyle but she said she never knew the victim was renting a room from her tenant.

“We could have taken a picture ID of the lady or check to see if she had a car registration,” said Boyle.

10News learned the victim and the man have three children together and they all live in Mexico.

Police discovered the man is not a U.S. resident. They also cannot locate the missing child’s biological father.

Rodriguez is not Alejandra's father. He may be driving a gray 1985 Honda Accord with license plate 1MGA355, Sferra said.

He is Hispanic, 5 feet 8 inches and 170 pounds with black hair and brown eyes. He was last seen wearing blue jeans and a T-shirt.

Anyone who sees Alejandra or Rodriguez is asked to call police at (619) 531-2000.