iPhone 4s won't turn on and makes beeping noises?

My cousin just gave me his old iPhone 4s and it won't turn on, or show anything on the screen when I plug it into my charger. However, after about 10 minutes of being plugged it, it keeps making intermediate beeping noises every 5 seconds and won't stop. I've tried holding the home and power button down, and nothing happens. What can I do to fix this problem?