One day Nina and her family were held hostage at her house the phone rang and the criminal let the Nina a nswer the and she said"HI mom I'm at home if its not an emergency I'll call you later if you dont need help with anything I'll call you later I'm going to sleep now. 

5 minutes later the police arrive how did she call the police?

She held the mute button except the words home emergency help       https://www.youtube.com/watch?v=Ke_ae1qYFY4