DEADLINE DAY: Mexican border wall bids due today pic.twitter.com/JXtH0Rmj7N — FOX & friends (@foxandfriends) April 4, 2017

Bids are due today for the first design contracts for President Donald Trump's proposed wall along the U.S.-Mexico border.

The Department of Homeland Security has asked companies to submit bids for a 2,000-mile barrier to prevent illegal immigrants and drug traffickers from entering the U.S.

Bidders must have done border security or similar projects worth $25 million in the past five years to qualify.

A U.S. official, who spoke on condition of anonymity because the details haven't been made public, said four to ten bidders are expected to be chosen to build prototypes.

They will be constructed on a roughly quarter-mile strip of federally owned land in San Diego within 120 feet of the border, the official said.

The government anticipates spending $200,000 to $500,000 on each prototype.

The department laid out some basic parameters for the wall. It should be 30 feet high, but bids for an 18-foot structure will be considered. It must run at least six feet underground to make tunneling more difficult.

It also must also be able to endure at least 30 minutes of attempts to bore through it with a "sledgehammer, car jack, pick axe, chisel, battery operated impact tools, battery operated cutting tools, Oxy/acetylene torch or other similar hand-held tools."

In addition to bids, the Department of Homeland Security is collecting general suggestions from outsiders, including contractors, think tanks, universities and even members of the public.

Building a wall on the Mexican border was a cornerstone of Trump's presidential campaign and one of his most controversial policies.

Watch the "Fox & Friends" report above.

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