TUCSON, Ariz. (CBSNewYork/AP)– Immigration reform advocates say that immigrant deaths while in custody are on the rise, and a lack of proper medical care is to blame.

The ACLU, Detention Watch Network and National Immigrant Justice Center examined reports filed by an ICE review board in charge of investigating detention deaths, finding that U.S. Immigration and Customs Enforcement has for years failed to provide adequate medical care at detention facilities.

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The reports are from 2010 to 2012, but advocates say the problem is ongoing and getting worse.

Separately, ICE data from its website shows that there have been 155 in-custody deaths between October 2003 and Jan. 25, 2016.

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In Arizona, two people died while in custody last year, raising concerns among immigrant advocate groups.

ICE said in a statement that it investigates all deaths and is committed to “providing a safe and humane environment” for detainees.

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