President Barack Obama signed the Blue Alert Act into law Tuesday.

The new law works similar to the Amber Alert system, and will set up a nationwide network that will alert police immediately about a suspect wanted for killing or harming a police officer.

The law came about after the ambush-killing of New York City Police Officers Wenjian Liu and Rafael Ramos. Both men were killed by a man from Baltimore who posted online that he was on his way to New York to harm police.

Patrick Colligan, president of the New Jersey PBA, supports the law and says it could save lives.

"Now you have a nationwide alert where everybody can look out for a car or look out for a suspect. Maybe even get a picture out right away," he says.

The alert system is now under development by the Justice Department.