A campaign to get advertisements for gay hookup site Squirt.org removed from Washington, D.C. metro stations by conservatives and concerned parents is so far coming up empty.

An online petition calling for their removal has garnered over 1,500 signatures at time of writing.

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Conservative news site CNSNews.com reports a Metro representative told them the ads could not be removed because regulating content would violate the advertiser’s First Amendment rights.

They point out that the Metro bans religious, political and advocacy advertising, which is true.

That decision was made last year after a group tried to buy space to place a cartoon of Muhammad as an advertisement, which many Muslims find offensive. The same group trying to place the ad was responsible for the “Draw Muhammad” contest that led to a shooting in Texas.

The Metro then closed what they labeled as “issue-oriented” advertising for the rest of the year, which they then decided to continue indefinitely.

“The advertiser purchased a total of five ads in three stations through August 7. Metro has not received any customer complaints to date,” Metro spokesperson Morgan Dye told CNSNews.com.

The petition reads as follows:

Dear D.C. Metro Board and Advertising Committee, I am writing to express my shock and displeasure at discovering that you are currently promoting an inappropriate homosexual hookup ad in the Metro System. This complaint refers specifically to the advertisement for “Squirt.org,” a so-called homosexual hookup website. This advertisment is posted in multiple places in the Dupont Circle Red Line Station, and is likely found in other stations throughout the city. You can view a copy of the ad by following this link. Not only does the advertised website encourage homosexual hookups and video chats, it also provides an avenue for interested customers to find a “casual” hookup partner in a public place, such as a bar or a public restroom. This activity, commonly known as “cruising,” often leads to illegal prostitution and indecent exposure charges. By posting this advertisement, the D.C. Metro is facilitating illegal activity and exposing young people to sexually explicit content . Last year, the Metro Board banned all religious advertising in the Metro System. Religious advertising is usually uplifting, encouraging, and moral. There should not be a blanket ban on all religious advertisements. To the contrary, advertisements such as this one are morally corrupt and encourage dangerous and illegal activities. Stop subjecting your customers – especially children and adolescents – to this inappropriate sexual advertising, and please issue an apology to all of your customers who have already been affected by this advertisement. Sincerely,

[Your Name]

This is not the first time Squirt ads have made a stir.

They have previously caused concern in Dallas, were censored in Miami and were pulled in Toronto and Cardiff.

A video of an ex-marine smashing the glass protecting one of the ads and throwing it into the street once accessible went viral last year.