I think before reporting it as child abuse, I'd get some advice about whether this actually constitutes child abuse from professionals and what can be done (and the approach would differ depending on whether you and your kids live with your husband or not - it's not clear from your post). You said this behaviour started only lately - it could be a result of stress at work and maybe counselling would help. And as Gracey said, there are some people who are just not prepared for the sheer noise children make and the energy required to care for them...and some cultures condone that kind of behaviour. So they need to be made aware that their behaviour is wrong and unproductive but may not be as drastic as classifying it as mental problems (again, I think only professionals can diagnose mental problems).
Apart from the links Thanka2 mentioned, you could try this NGO called Against Child Abuse (
http://www.aca.org.hk/) to get some guidance on how to approach your situation.