A free mobile app being used by millions of school age children and teens is under fire again after police link it to the murder of a 13 year old girl in Virginia.

"Kik Messenger" is an anonymous messaging app that allows users to communicate with strangers. It requires no phone number or email address; users exchange user names to communicate in private chat rooms.

Police in Virginia reported it was this app that connected 13 year old Nicole Madison Lovell with two people who killed her. Police have charged two Virginia Tech freshmen with premeditated kidnapping and murder.

Kik Messenger was launched in 2009 to give people the ability to communicate with others without using their cellphone's data plan or sms limits.

However, the anonymity became attractive to sexual predators and online cyberbullies because it is difficult for police and other law enforcement agencies to get access to the data.

The company is also located in Canada making it even more difficult to serve subpoenas in the event a crime is committed.

Earlier this year investigators have pointed to the Kik app when discussing at least 5 serious crimes involving children. In one of those incidents an

Alabama man attempted to check a young girl out of her school after the two met on Kik. He was charged with statutory rape and attempted kidnapping.

It prompted Blount County (Alabama) District Attorney Pamela Casey to issue a warning to parents over video, begging them to check their children's phones and delete the app immediately. "Nothing good can come of it," she told parents.

Kik developers have cooperated with police in the Virginia disappearance and killing of the 13-year-old Lovell.

On the company's website it claims 40% of America's young people currently use Kik

Messenger and there are some 240 million users worldwide.