EDISON - The U.S. Department of Education is sending a warning to schools, colleges and universities nationwide in response to several high-profile cases of bullying.

In letters going out today, the agency tells schools they could be violating federal anti-discrimination laws if they tolerate or fail to adequately address ethnic, sexual or gender-based harassment.

The department says it is responding to what it senses as a growing problem in the country's schools.

Among the cases are the suicides of an 18-year-old Rutgers University freshman, Tyler Clementi, and a 15-year-old Massachusetts girl.

Harassment based on race, color, national origin, sex or disability that creates a hostile environment and is encouraged, tolerated or not adequately addressed can be in violation of civil rights statutes.

Yesterday, New Jersey lawmakers introduced a bill to toughen the state's anti-bullying laws. A bipartisan group of lawmakers touted the "anti-bullying bill of rights" targeting public schools and colleges.

NJ lawmakers want to toughen anti-bullying law

AP wire services contributed to this report.