A doorbell camera in California captured what police are calling a man’s brutal assault on his ex-girlfriend on Sunday night, leading to his arrest on attempted murder and kidnapping charges.

The horrifying scene begins with the victim frantically pounding on a neighbor’s door for help as Robert Michael Mendez, 27, closes in on her, according to footage obtained by KCAL.

The neighbor’s doorbell camera captured the video and audio of Mendez’s alleged attack.

“No, no, no!” the woman can be heard screaming, as Mendez appears to grab her by the hair and drag her away from the neighbor’s home.

“I thought she was going to die. It was really traumatic to watch,” said neighbor Tammy Raycraft.

“We looked out the side window over here and witnessed him stomping on her, pulling her by her hair … it was awful.”

Another neighbor who witnessed the attack called 911.

But when cops arrived that night, the two were nowhere to be found, the report said.

It wasn’t until the next day that Mendez was collared when neighbors told authorities they suspected it was him on video.

“Within minutes, there were several police cars and he was in handcuffs, and she was taken away by paramedics,” said Raycraft.