A conservative group says it has been sending men into women's toilets at Target stores to protest against the company's policies toward transgender people.
In response to recent laws in US states, the retailer said transgender people are welcome to use the toilet of their choice at its stores.
An online petition urging a boycott of Target has over a million signatures.
The American Family Association (AFA) told Breitbart News it was testing Target's new policy.
"We've already had people ... going into Targets and men trying to go into bathrooms. There is absolutely no barrier," said Sandy Rios, AFA's director of government affairs.
North Carolina and Mississippi have passed laws that require people to use public toilets that correspond to the sex listed on their birth certificate.
Many businesses and entertainers have criticised the measures as discriminatory.
Musicians have cancelled concerts in the states and several companies have pledged to curtail their business in North Carolina.
Some supporters of laws that restrict the use of public toilets said allowing transgender people to choose their restroom could lead to women and children being attacked.
They said they feared that men could pose as transgender people and use legal protections as a cover.
In recent days, YouTube has seen an uptick in videos showing men entering women's toilets.
Police were called to a Target store in Illinois on Monday for an "active shooter situation".
However, when they arrived they found an unarmed man protesting against Target's toilet policy.
Michael Merichko, 39, was charged with disorderly conduct.