U.S. authorities say they are modifying how they enforce a key immigration program to concentrate on the most serious criminals.

U.S. Immigration and Customs Enforcement Director John Morton says authorities are listening to concerns from local and state governments about the Secure Communities program in which law enforcement agencies share fingerprint information with U.S. immigration authorities.

Federal immigration authorities say the program will be modified to focus more on illegal immigrants who are serious criminals.

Critics and several local and state governments who are against the current program say it does not differentiate between minor offenders and serious criminals. They say it discourages immigrants from reporting crimes out of fear they could end up being deported.