PHOENIX -- Illegal immigrant sex offenders sneaking across the Mexican border into the desert Southwest revealed a problem with the way criminals are being deported, a CBS 5 investigation uncovered.

When an illegal immigrant commits a crime in Arizona he or she is sent to jail or prison and then deported back to Mexico. However, 5 Investigates uncovered that instead of dropping the offenders deep into Mexico; they are being dropped off right at the border.

5 Investigates videotaped an Immigration and Customs Enforcement van carrying two illegal immigrants, who just finished serving prison, to the border.

Upon arriving at the border, the offenders stepped out, were handed their belongings and set free.

5 Investigates interviewed the men on what they planned to do next; one man said he planned to turn around and attempt to go back to California where his family lives.

Federal officials, such as Katrina Kane from ICE, said they face difficulties as their ways of deportation are limited.

"It's not the only way that we're deporting them. It's one of the ways we are deporting, you know, individuals to Mexico," said Kane.

Others disagree and believe there are better ways to ensure people charged with sex crimes do not re-enter society.

Scott Berkowitz of RAINN, an organization that lobbies Congress of behalf of rape victims, said he believes prison may be the best way to deal with those charges with sex crimes.

"The best thing we can do is keep them in prison for a much longer time," Berkowitz said.

Border Patrol agents report seeing illegal immigrants every night attempting to cross the border, many of them sex offenders.

Last year, on a small sector of thoroughfare near Nogales, Border Patrol caught nearly 400 offenders trying to sneak across in this one area alone.

Border Patrol Agent Mike Scioli revealed to 5 Investigates just how frequent these convicts enter back into the country.

"Within just the last week, we caught three major sex offenders and it was anything from lewd acts with a minor to child molestation; I believe one was a rape victim or sexual assault," Scioli said.

Agents said they identified sex offenders from North Carolina, Oklahoma, Nebraska, Iowa and California that were deported to Mexico and then turned around and re-entered the U.S. at the Arizona border.

Police said the Chandler rapist was one of these offenders.

The Chandler rapist is an illegal immigrant who was deported twice from California to Mexico.

Sex offenders and other ex-cons caught re-entering the U.S. face new prison terms up to 20 years.

However, the convicts 5 Investigates interviewed said the consequences of getting caught will not stop them from attempting to re-enter the U.S.