The prototypes form a tightly packed row of imposing concrete and metal panels, including one with sharp metal edges on top. Another has a surface resembling an expensive brick driveway.
Companies have until Oct. 26 to finish the models but Border Patrol spokesman Theron Francisco said Thursday the last two came into profile, as crews installed a corrugated metal surface on one model on a dirt lot just a few steps from homes in Tijuana, Mexico.
As the crews worked, three men and two women jumped a short rusted fence from Tijuana into the construction site and were immediately stopped by agents on horseback.
Francisco said there have been four or five other illegal crossing attempts at the site since work began Sept. 26.
The models cost the government up to $500,000 each.