Police are searching for a 4-year-old boy who, they said, was taken by his father.

Cristian Morales-Vanfossen was last seen Wednesday.

According to court documents, the boy's father, 34-year-old Abdon Morales, assaulted Cristian's mother on Wednesday. Detectives said Morales first tried to cut the woman's throat and then choked her.

Cristian's mother said that, after she was attacked, Morales left her home with their 1- and 4-year-old sons.

The mother said Morales tried to make a deal with her to drop the charges in exchange for the children. She said she was able to get the 1-year-old back, but not the 4-year-old.

Morales was arrested on an assault charge. He is being held in the Harris County Jail.

According to the mother, Morales said he gave the boy to a friend. Investigators said Cristian may be in Mexico.