The U.S.-Mexican border will be lined with 1,800 towers equipped with sensors that can detect when a person steps onto American soil, a newspaper report said on Friday.

Infrared cameras will sense the body heat of possible intruders, and radars will track vehicles that may carry illegal immigrants and drugs into the United States, the Los Angeles Times reported.

It said the towers could lead to a virtual fence along 7,500 miles of the U.S.' borders with Mexico and Canada.

The 67-million-dollars contract to build the towers has been awarded to Boeing. But analysts said the project could be expanded to more than 2.5 billion dollars.

Boeing beat out three of the nation's largest defense corporations and a Swedish cellphone maker for the contract - part of a larger homeland security initiative to stem the flow of illegal immigrants into the country, according to the paper.

When the project is completed, Boeing said, its towers would leave little of the now-porous borders undetected, creating a high- tech fence longer than the Great Wall of China.

"What we are looking to build is a 21st century virtual fence," Homeland Security Secretary Michael Chertoff said at a news conference announcing the contract.

Source: Xinhua