[tyingq]

It does have risks since the 3 digit dial looks distinctive. Or things like redial that could give it away.

[tata71]

9110000000000 as many times as needed.

[noodlesUK]

Does this actually work on mobiles?

[chenxiaolong]

Yep. Same thing with 1800xx911xx (and so on). I made that mistake as a kid with my parents' old unactivated phone. That's when I learned any mobile phone can call emergency services.