A suspected kidnapper wanted in connection with a 16-year-old California girl's disappearance might be armed with homemade explosives, authorities said Thursday.
San Diego County Sheriff's Capt. Duncan Fraser said evidence recovered at James Lee DiMaggio's home east of San Diego, Calif., suggests he might have fled with explosives, according to NBC San Diego.
The search for Hannah Anderson and her 8-year-old brother, Ethan, now spans four states, Canada and Mexico.
The two children have been missing since their mother’s death.
Fraser said it is possible DiMaggio had an "unusual infatuation" with Hannah and this might have driven the 40-year-old to flee with her from his burned home on the California-Mexico border.
"That is kind of a working theory, that it may be something of a motivator," he added. "It's definitely something that we're looking at."
Marissa Chavez, 15, told The Associated Press that a couple months ago she had witnessed DiMaggio tell her friend that he had a crush on her and would date her if they were the same age, as they drove home from a gymnastics competition.
"She was a little creeped out by it. She didn't want to be alone with him," Chavez told the wire service.
On Sunday, police discovered the burned remains of her mom, Christina Anderson, 44, in a log cabin-style home in Boulevard, Calif. Along with Anderson’s body, police also found the body of a child that has yet to be identified, but authorities believe it may be Ethan’s.
Amber Alerts were issued in Oregon and Washington on Wednesday for the two kids after DiMaggio’s car was believed to have been spotted in Northern California. The alert did not say whether DiMaggio or either of the children was in the car. An alert was also posted in Nevada on Thursday.
DiMaggio is believed to be driving a blue Nissan Versa with California license 6WCU986.
"We're very concerned for Hannah. We believe she is in grave danger," said San Diego homicide Lt. Glenn Giannantonio, according to NBC San Diego.
The FBI and various state and local law enforcement agencies are assisting in the investigation.
On Tuesday, Anderson’s husband, Brett, pleaded for DiMaggio, a family friend who owned the house that burned, to release his daughter.
“The damage is done. I’m begging you to let my daughter go, you’ve taken everything else,” Anderson said from a podium in front of the San Diego Sheriff’s Department.
Sheriff's officials told NBC San Diego that Christina Anderson had a “close platonic relationship” with DiMaggio. Neighbors told the station had he moved to the area five years ago from the city. A neighbor told The Associated Press that Christina and Brett Anderson had recently separated.
DiMaggio is described as white, 5 feet 9 inches, 150 pounds, with brown hair and brown eyes. He may have shaved off a mustache and beard, detectives told the paper.
Anyone with information about this incident is asked to call Crime Stoppers at (888) 580-8477.
NBC News' Andrew Rafferty, Olivia Santini, Henry Austin and The Associated Press contributed to this report.