A terrified mother has found an online live-stream of her twin daughters' bedroom.

A Houston mother-of-three was horrified to discovered footage from a camera in her children’s bedroom was being live-streamed to strangers online.

The mother – who chose to remain unnamed – said she never dreamed someone would hack into her family’s home surveillance system, which had been used to supervise her eight-year-old twin daughters and her six-year-old daughter.

“I have cameras to protect my kids and I kind of feel like we failed them,” the mother said.

“We didn’t protect them. We actually put them in harm’s way,” she told local news network KPRC.

A woman in Oregon was using the app “Live Camera Stream” when she stumbled on footage coming out of the twins’ pink bedroom.

She used Facebook to track down the family and warn them to turn off their cameras.

The mother immediately shut down the feed, but has no idea how many people viewed it nor how the hack occurred in the first place.

“I mean people are watching what they do 24/7 and who knows who’s watching it?”

Security experts say such attacks are not uncommon, no matter how high-tech the system is.

“If you don’t change the default password settings, they’re the same for everyone who bought one of those devices,” University of Houston’s Mary Dickerson told the network.

“That means there are thousands of people around the world who know what you user ID and password is.”

She said the best way to protect yourself was therefore to change passwords regularly.