Hector Rívera spent five months in an immigrant detention center in Arizona, where he witnessed the treatment received by undocumented migrants in those facilities, most of which are administered by private corporations.

Rívera's story is one of several that are part of a report by the American Civil Liberties Union of Arizona that denounces the harsh conditions in the detention centers.

"They were five very difficult months. As people, we have the right to freedom, and to be in prison is very difficult for any human being, above all if you haven't committed any crime," the 27-year-old University of Arizona graduate said in an interview with Efe.

Only 5 years old when his parents brought him to the United States, Rívera made many sacrifices to get a college degree.

He was stopped in August 2010 for a traffic violation and classified as a "non-citizen," on the basis of which he was sent to the detention center in Florence, Arizona.

With his education and knowledge of English, Rívera helped others with the translation of documents while he was detained.

"Although I was not directly the victim of any kind of abuse, I certainly saw medical cases that ended up being a little more serious than if they would have been prevented initially," he said.

The ACLU report released last month - "In Their Own Words: Enduring Abuse in Arizona Immigration Detention Centers" - is based on 115 interviews over a period of two years.

The ACLU calculates that every day there are an average of 3,000 undocumented immigrants being held in the detention centers in Arizona.

Some relatives who had U.S. citizenship adopted Rívera before he was 15, but because of their lack of knowledge of the immigration system they did not request automatic citizenship for him, which placed his legal status at risk.

"What I remember most is missing my family so much and being locked up," said Rívera, who is already a legal resident of the United States.

Victoria López, an ACLU lawyer and the author of the report, said on Tuesday at a community forum in Tucson that the undocumented immigrants in the centers are the victims of unnecessary and prolonged detentions.

"According to figures from (U.S.) Immigration and Customs Enforcement, an undocumented immigrant spends an average of 37 days in a detention center, but the truth is that in Arizona the period is approximately four months," she said.

The attorney said that she had worked on cases of undocumented immigrants who were detained for up to two years.

Detention conditions depend in large part on the private company that administers the center and the level of supervision on the part of ICE, López said.

She said that in the last six months the number of undocumented immigrants being detained in Arizona has increased by more than 50 percent.

"I think it's important to share my story because when I entered the detention center I didn't know they existed. I imagine that there are thousands of people who don't know what's happening, and by speaking about this it becomes more real. Especially, in a country where human rights are so strongly defended," Rívera said.

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