Friends, family and fans weren't the only people blindsided by Demi Lovato's reported overdose on Tuesday (July 24)—longtime pal and fellow pop star Justin Bieber was just as shocked by the harrowing incident.

The singer was out and about in Los Angeles Wednesday afternoon when a TMZ cameraman caught up with him in a parking garage and asked him if he'd heard the news about Lovato.

The singer called the situation "terrible" and "very sad."

"I haven't talked to her but my prayers go out to her and her family for sure," Bieber continued, adding that he "thought she was sober."

On Tuesday, news broke that Lovato had reportedly suffered a drug overdose—initially believed to be heroin-related—at her home in Hollywood, and was subsequently rushed to the hospital after being revived by Narcan.

It's still unconfirmed what caused the overdose, though some reports suggest the singer had taken meth in the days leading up to the incident. Lovato is believed to be recovering in a Los Angeles area hospital, where a spokesperson said she is currently "awake" and "with family."

Celebrities Who Opened Up About Mental Health

More From 92.9 NiN