It happened in the 400 block of Madre Lane Friday morning.
"It didn't make sense to me because the door was shut," said Jenny Kay. "I thought it was a person so I was really nervous. I live alone."
After the cubs got inside, they couldn't get out. Officers were able to get the cubs out, who were soon reunited with their mom.
Video captured the cubs' mom arriving as officers showed up.
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"I'm so glad that the dogs are OK, that the cubs are OK," said Kay. "The police department and my neighbors are lovely, but it's really crappy and ridiculous. Like, do you guys know anybody who had a bear in their car? It's nuts."
Kay owns a market in Sierra Madre and said she wishes the cubs would've gone after her store instead.
"It's crazy. They could have come [to the store] and gotten a lot more food and a lot more things," she said. "Like, come to Mary's Market for good food and coffee, don't come to my car."