“This type of spending is irresponsible as our nation faces significant budget deficits and the men and women in the Border Patrol face cuts in overtime that are essential to their mission,” Barber said. “I have demanded immediate answers from the Department of Homeland Security on how and why these outrageous expenses were approved.”

The newspaper reported that the DHS paid nearly $600,000 apiece to build the 21 homes in Ajo, Ariz., where comparable homes sell for between $70,000 and $100,000.

Both lawmakers asked officials at the DHS to justify the spending by the time Congress returns from recess in September.

Grijalva also asked Secretary of Homeland Security Janet Napolitano to publicize how much the DHS paid private contractors in the past three years to incarcerate nonviolent immigrants in the United States illegally.

“The cost of these detentions … is surely high and getting higher each year,” Grijalva wrote. “These figures should be readily available to DHS policymakers for planning and budgeting purposes, and there is no reason Congress should not base its discussion on an accurate assessment of how much the status quo is costing us.”

Grijalva said it was crucial that lawmakers have this information as they continue to debate comprehensive immigration reform. The Senate passed a bipartisan immigration reform bill this summer with 68 votes. The House is debating if it will consider that bill or its own immigration reform measures.