How to report physical abuse at home?

My girlfriends parents are very abusive (hitting, scratching, throwing her, ripping off her clothes). They broke her iphone so I've sent her more (about 4) over the course of 6 months. She lives in another state (Texas), I live in Arkansas. I've been trying to urge her to report this but she's scared of what will happen after a report is made; she doesn't want to go to foster care. The only time she has a way to communicate is at night from around 12-6 AM from a brothers or sisters device (you can't call from the devices). It's only getting worse for her. She has marks on her chest and hips currently. I made her promise me she would make a report online and she did, but it has been over 24 hours with no response. What should I tell her to do?
Added (1). We are both 15 if that helps on any advice given
Added (2). I have photos of the marks, and have heard the abuse happen over the phone. I'm not that ignorant.

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