The Obama administration is preparing to end plans to gradually extend a high-tech "virtual" border fence along vast stretches of the 1,969-mile U.S.-Mexico border, at an estimated cost of $8 billion.

 

The project initially was designed to be completed by 2011 -- but that deadline slipped to at least 2014. The virtual fence is located at only two sites in Arizona, near Tucson and Ajo.

 

The project is reportedly ending because of cost overruns, missed deadlines and continued difficulties with technology that does not detect intruders as promised.

 

The 53 miles of high-tech surveillance equipment along the border at two locations in Arizona was designed to augment nearly 700 miles of pedestrian fencing and vehicle barriers built by the Bush administration and finished by the Obama administration along the U.S.-Mexico border in Texas, New Mexico, Arizona and California.