A 3-month-old baby boy has been found safe Tuesday after he was taken from his Northern California home in what police believe was a premeditated kidnapping.

Three suspects are in custody, police said.

Brandon Cuellar’s kidnapping was reported around 1 p.m. Monday by his grandmother, who was watching the baby while the mother was at work, San Jose Police Sgt. Christian Camarillo said.

The grandmother said she came home, took Brandon inside the apartment and went back to the car to unload groceries, Camarillo said.

In that “short amount of time,” a man went into the apartment and took the little boy, he said. Police released footage of the man they say was seen on surveillance video leaving with the 3-month-old.

Camarillo said the suspect brought a baby carrier with him to the home.

“We believe this was planned. It’s not some random act,” he said.

Camarillo said Tuesday that police are speaking with a female person of interest, but added that she’s not been “formally charged yet.”

“This is a person that was with the grandmother yesterday when they went shopping. She was present at the apartment complex when this happened,” Camarillo said.

“That person has changed their story a couple of times — a lot of inconsistencies,” Camarillo said.

ABC News’ Bonnie McLean contributed to this report.