After Facebook that included images depicting her parents’ persecution under the Khmer Rouge communist regime in Cambodia, Twitter has followed up with its own ban.

A backlash prompted by media coverage led to Facebook changing its mind last week and approving the ad by Elizabeth Heng, who is challenging incumbent Democrat Jim Costa for the 16th District seat in California’s Central Valley.

But Twitter determined the ad is “ineligible to participate in the Twitter Ads program” because the content violates its ban on “that which is offensive, vulgar, or obscene,”  citing Heng’s campaign.

The ad contains footage of the Cambodian genocide by the Khmer Rouge under which Hengs parents suffered before fleeing to the U.S. from Cambodia to escape the communist genocide.

The campaign asked Twitter for further explanation, but the social media giant responded with the same message, this time highlighting in bold the word “obscene.”

After being pressed further for an explanation, the Twitter Ads Support team said it could “no longer assist or support any further requests.”

After Facebook’s rejection, Heng said that neither Facebook “nor any other company in the tech industry get to silence our stories.”

“We’ve seen it over and over again with Republican candidates and organizations. This kind of censorship is an attack on the freedoms that we have as Americans to express what we believe in, and we must hold Facebook accountable,” she said.

A Facebook representative, according to Heng’s campaign, originally said the ad contained content too “shocking, disrespectful or sensational” for the platform.

that Facebook banned a pro-life video ad by a judicial candidate, giving the same explanation.