Criminals broke a window to gain access to their property earlier this week (begs22Mar21), but made a prompt retreat when they realised the "Senorita" collaborators were present.
According to TMZ, police were called but the suspects had gone by the time they arrived.
However, they didn't leave empty handed, reportedly grabbing the keys to Shawn's Mercedes-Benz G-Wagon and making off with his SUV (Sports Utility Vehicle) as they left.
The case is currently under investigation, but cops have yet to make any arrests.
Representatives for Shawn and Camila have yet to comment on the security scare.
The pop stars, who have been dating since 2019, have been isolating together throughout the COVID-19 pandemic.
Shawn Mendes credited his quarantine with Camila Cabello for inspiring him to spend more time with his loved ones.
"I was on such a speedy path down one way with blinders on, and I wasn't keeping in touch with my family and friends," he told Elton John in an interview for VMan Magazine, "but when I landed with Camila, immediately she had her family around more."
"She's all about the family and friends, and it really made me (think) like, 'Oh, I should call my mom...' I felt a little bit alone out there and she changed that for me."
In a different interview, the singer admitted he was initially panicked when the lockdown first hit last March. "And then when I started to settle in to how nice it is to be in the same place every night, to have a movie time, to cook dinner with the family and to do laundry," he explained.