After receiving threats from fans of former President Donald Trump, a butterfly sanctuary caught in the middle of contentious conspiracy theories about "illegal" immigration to the United States announced it would close its doors on Thursday, citing security concerns.

The National Butterfly Center in Texas, which is located on the banks of the Rio Grande that separates the United States and Mexico, filed a lawsuit to stop the construction of the border wall that has become a focal point of Trump's presidency, saying it would endanger the habitat of the winged insects.

The private sanctuary's gardens are home to more than 200 species of butterfly as well as bobcats, coyotes, peccaries, armadillos, and Texas tortoises. 

Conspiracy theories, which have been attributed to the far-right group QAnon by US media, have it that the sanctuary is aiding in the influx of migrants to the US.

Glassberg believes the facility was already closed between January 28 and 30 due to "credible threats" related to a rally attended by supporters of the former president in neighboring McAllen.

Messages circulated accusing the center of supporting smugglers in delivering migrants to the US. Several right-wing protesters have shared footage of themselves in front of the shelter on social media.

"We don't think the threat has passed," the sanctuary's executive director Marianna Trevino Wright told AFP on Wednesday, citing repeated "provocations" from these individuals.

Wright said she feared the allegations against the center would eventually push someone to "take action".

"We look forward to reopening, soon, when the authorities and the professionals who are helping us get past this situation give us the green light," Glassberg said in the statement, noting that employees would continue to receive their salaries during the closure. 

The QAnon movement originated in 2017 with allegations that the Democrats were running a satanic kidnapping and sex-trafficking ring, and it has been blamed for inciting a disturbance at the US Capitol on January 6, 2018.

It is worth noting that Trump has never condemned the movement.