MIRAMAR BEACH — The first section of a border wall between the United States and Mexico, built with part of the money raised in a GoFundMe campaign started by local wounded warrior and conservative activist Brian Kolfage, is under construction near El Paso, Texas.

Kolfage, an Air Force veteran who lost both legs and an arm in a 2004 rocket attack on an air base in Iraq, announced the private border wall funding effort late last year. Initially, the effort was focused on a GoFundMe campaign that aimed to raise $1 billion to assist federal government efforts to build a wall. While the GoFundMe campaign is still active, within weeks of its inception Kolfage changed the focus toward a private wall construction through the Florida-registered nonprofit organization We Build The Wall Inc.

Construction of the steel bollard and concrete wall section, which will cross somewhere between a half-mile and a mile of land, began at sundown Friday and is expected to be completed sometime today, according to Dustin Stockton, a conservative activist and Tea Party organizer who is part of the team leading the We Build The Wall initiative.

"We're extremely excited to be able to deliver on the promise that we made," Stockton said Tuesday.

The wall section, which includes an adjacent paved road and will also feature electronic sensors and anti-tunneling technology, will cost between $6 million and $8 million, according to Kolfage. That's about one-third of the nearly $23 million the GoFundMe campaign and other funding sources have raised for the wall effort.

But Kolfage said Tuesday that there were some unique cost considerations in building the first section of the wall. The structure traverses a hilly area between the Rio Grande and a sheer cliff near Sunland Park, New Mexico. The wall being erected along that stretch of border cost $2 million, he said, but excavation work in the hilly area added the considerable extra cost.

Nonetheless, We Build The Wall Inc. chose that part of the border for its first section of wall because the area is notorious for large numbers of people and drugs crossing into the United States. The land for the wall was deeded to the nonprofit organization by the owners of the American Eagle Brick Company, whose land the wall crosses. The owners have reported thefts and other problems related to migrants illegally crossing the border, according to Kolfage.

"It's a very bad area," said Kolfage, who added that on a recent visit there he was able to cross the border into Mexico and come back into the United States in his wheelchair. Also according to Kolfage, there is a parking lot on the Mexican side of the border at the wall construction site.

While the initial section of wall carries a significant cost, Kolfage and Stockton said that We Build The Wall Inc. is confident that construction will prompt additional donations to the GoFundMe effort in addition to other private donations.

"We ... believe we're going to raise a lot of money off this section of wall," Kolfage said.

"This is just our first project," Stockton said. "We expect to continue."

We Build The Wall Inc. is working with property owners in four states to acquire property for wall construction, and Kolfage said that future sections of the wall won't cost as much as the first section because they won't have the terrain challenges.

The GoFundMe effort did show an uptick in contributions Tuesday, largely in the range of $20 to $100, but also including a $7,500 donation.

But as recently as two weeks ago, Kolfage and We Build The Wall were facing a rising tide of skepticism, even among donors, about construction of the wall.

“I only gave a few dollars toward this venture — just what I could afford," one supporter posted on the initiative's Facebook page earlier this month. "Nonetheless, I hope we see some movement on the wall construction soon. ... Brian, put people’s minds at ease, and at least show us some permits. Just that gesture will calm the nervous. Please?”

In the wake of that unease, Kolfage promised that evidence of progress would come, although We Build The Wall Inc. did not provide specifics until putting out word during the Memorial Day holiday weekend that construction had begun. In the days since, We Build The Wall Inc. has offered tours of the construction site to various media outlets, including the El Paso Times and CNN. On Tuesday Kolfage said he was taking a New York Times photographer to the site.

Kolfage said Tuesday that the site for the next section of border wall has already been chosen, but as with the first section he declined to provide any advance notice.