U.S. immigration officials, who for months have insisted that states sign up to participate in a controversial program to identify and deport immigrants who commit crimes, abruptly changed their approach Friday and terminated agreements with nearly 40 states.

In a letter to governors, John Morton, head of Immigration and Customs Enforcement, said the government was terminating Secure Communities agreements with nearly 40 states, including Arizona, after determining that the federal government does not need the agreement or cooperation of state officials to legally run the program.

In the letter, a copy of which was obtained by The Arizona Republic, Morton said the decision to terminate the agreements would not affect the operation of the program.

Routine fingerprints of crime suspects by local law enforcement are automatically screened by federal immigration authorities.

The Obama administration, as it tries to demonstrate that it is tough on border security and illegal immigration, has pushed to expand the program nationwide.

The decision to terminate the agreements and move forward without them comes after Democratic governors of several states said they would no longer participate in the program amid concerns that it makes immigrants afraid to report crimes to police.

It also shows that the administration is determined to move forward despite objections from immigrant advocates that the program also is deporting thousands of low-level offenders in addition to serious criminals.

"ICE continues to work with its law-enforcement partners across the country to responsibly and effectively implement this federal information sharing capability and plans to reach complete nationwide activation by 2013," Nicole Navas, an ICE spokeswoman in Washington, D.C., said in an e-mail.

Arizona was among the first states to embrace the program, which was launched in October 2008.

All 15 counties in Arizona are participating in the program, which is currently in effect in more than 1,500 counties in 43 states.

Under the program, the fingerprints of every person booked into jails are shared with the Department of Homeland Security. Immigration officials screen the fingerprints to identify immigration violators and illegal immigrants so that they can be arrested and deported.

Immigration officials said they don't need the cooperation of state officials because local law enforcement, as a matter of practice, run the fingerprints of crime suspects through an FBI database to see if they are wanted in connection with other crimes.

The FBI will relay those fingerprints to the Department of Homeland Security.

The program has resulted in the deportation of more than 15,000 immigrants from Arizona and more than 101,000 immigrants nationwide.

Through April 30, more than 77,000 immigrants convicted of crimes were identified through the program and removed from the country, according to ICE.

That figure includes more than 28,000 convicted of aggravated felonies such as murder, rape and the sexual abuse of children.

Still, the program has faced mounting criticism from immigrant advocates who said it takes a dragnet approach to immigration enforcement that results in the deportation of traffic violators and other low-level offenders in addition to serious criminals.

An Arizona Republic analysis of ICE data in March found that 60 percent of the illegal immigrants deported nationwide during the first 2� years of the program had either no criminal record or had been convicted of low-level offenses.

Sixty-six percent in Arizona had no criminal record or were low-level offenders.

Salvador Reza, an immigrant advocate in Phoenix, said he was disappointed that the administration is moving forward with the program.

"The Secure Communities program should be eliminated, not made mandatory," Reza said. "The program is causing a lot of havoc. It does not differentiate between a killer and a jay walker. It's tearing apart families."

In June, Morton said ICE was revamping the program to make sure it focused on the government's primary goal of identifying and deporting serious criminals, but he emphasized that the changes would not restrict the program from deporting less-serious offenders.

He also said the program was mandatory even though ICE officials earlier had portrayed the program as voluntary and said states could opt out later if they wished.

He said then that the number of criminals and serious offenders deported under the program has been increasing, while the number of non-criminals removed through the program has been decreasing.