Police in the city of Orange say the suspect took off when they went to his office to inquire about the woman, who has filed a paternity suit against him.
The chase ended after his car ran over spike strips on the southbound 5 Freeway at Camp Pendleton. The man, identified as Shazer Limas of Orange, finally gave up 45 minutes later. The freeway has since reopened.
The incident backed traffic up for miles. The girlfriend, Arlet Hernandez, and her two children remain missing.
Police call Limas a person of interest.
"It definitely raises our level of suspicion that he would lead us on a pursuit, and then there be a stand-off at the end of the pursuit. Yeah, we're concerned for the well being of Arlet and the two children right now," said Orange police Sgt. Dan Adams.
Police say they had been searching for 30-year-old Hernandez and her two sons, ages three months and two years, all afternoon.
Anyone with have information on their whereabouts are urged to call 911.