Update at 4:10 p.m.: This story was revised to include new information from the National Butterfly Center executive director in Mission.

The National Butterfly Center, which is fighting to prevent an extension of the border wall through its property, announced late Sunday on Facebook that construction equipment has started showing up next to its property.

A photo taken Sunday, Feb. 3, 2019 shows construction equipment parked on land immediately to the east of the National Butterfly Center in Mission, Texas. (Lorri Burnett)

The construction is not directly tied to the current impasse between President Donald Trump and Democrats over Trump's demand for $5.7 billion in border wall funding; Congress last March approved more than $600 million for 33 miles of new barriers in the Rio Grande Valley. The U.S. Customs and Border Protection has said it intends to start building the wall this month.

Marianna Wright, the National Butterfly Center's executive director, said in a phone interview Monday she has seen a "dramatic increase in the presence of law enforcement" officers — both local and federal — along the levee near the Rio Grande.

Opponents of the wall construction had also convened in the area near the center's property, Wright said.

"Honestly, I have no idea what to expect," she said.

The 100-acre nature center, located in the border town of Mission, describes itself as "the premier location in the United States to experience the beauty, drama and emotion of wild butterflies."

The butterfly center has been in a fight to prevent federal authorities from going through with construction of the portion of the wall that would cut through its property. The National Butterfly Center's Facebook post promised legal action. But it's unclear if the center can do anything to stop the federal government from proceeding with construction.

Members of the Carrizo/Comecrudo Tribe join with other opponents of wall construction convened near the river and made their way about 3 miles down to the National Butterfly Center to march in protest on Monday, Feb.4, 2019 in Mission, Texas. (Delcia Lopez / The (McAllen) Monitor)

1 / 2The National Butterfly Center in Mission is expected to be plowed over to clear the way for President Donald Trump's border wall after the Supreme Court rebuffed a challenge by environmental groups.(Suzanne Cordeiro / Agence France-Presse) 2 / 2A bend in the Rio Grande is seen from a Texas Department of Public Safety helicopter on patrol over in Mission.(2014 File Photo / The Associated Press)

Under laws passed since the 9/11 terrorist attacks, the Department of Homeland Security has said it can override federal environmental regulations to build barriers at the U.S.-Mexico border.

The Center for Biological Diversity — a nonprofit based in Tucson, Ariz. — is suing the Trump administration to challenge border-wall construction in the Rio Grande Valley, as well as near the Santa Teresa Port of Entry in New Mexico and California.

The lawsuits challenge the administration's decision to speed construction by waiving of dozens of environmental, health and safety laws. In addition to the National Butterfly Center, the Texas waivers allow walls to cut through the Lower Rio Grande Valley National Wildlife Refuge, Bentsen-Rio Grande State Park as well as other private property.

All of the cases are still pending.

Information from The Associated Press was used in this report.