Philippine website - free advertising has unadministrated chat with abusive and sexual content

There is a website listed with dot ph offering free classified ads. We have just opened a new business and in the shouting chat of this website one person is daily trying to damage our business with saying like this place has been closed by the health department because of rats and other health hazards, the owner is a Nazi, the food is contaminated,etc. etc. Our place is well well maintained Deli and Cafe and we are people with excellent recommendation. Now this site has no control, you can use any name and he is changing name nearly daily. The worst part of the site is that people are racists there specially some person mostly foreigner have used abusive language for the Philippines. Other ask openly: Any schoolgirl free today. I pay you handsomely and much worse. What can be done to get this site closed or at least the administrator being warned to control the site. Any expert on the matter your asssistance is appreciated.