A Christchurch teenager, whose name has not been released, was denied bail on Monday over charges that he had posted a photograph of Al Noor Mosque, one of the two that were attacked, a week before the shootings, with the caption “target acquired.” He was also charged with reposting the video.

Each could spend as much as 14 years in jail if found guilty.

And a woman in Masterton, on the North Island of New Zealand, was arrested over comments she made on her Facebook page after the attacks. The police told The New Zealand Herald that they had yet to decide whether to charge her under the Human Rights Act, a rarely used provision that prohibits writings that incite racial disharmony. If charged and convicted, she would face a fine of 7,000 New Zealand dollars, or about $4,800.

Criminal charges were not the only possible consequence of having publicized the attack. An Auckland medical clinic said on Thursday that it had suspended a senior doctor, pending an investigation, after being alerted to anti-Islamic comments he made on a blog several years ago.

Andrew Scott-Howman, a New Zealand employment lawyer, said he had seen a growing number of cases in which workers were accused of “bringing their employers into disrepute,” which he said was a more subtle charge than outright criminal activity.

“It’s hard to know where the line is drawn,” he said, adding that employment law was still developing in the area.

The cases underscore the challenge that social media companies face in thwarting and deleting objectionable activity on their platforms. Analysts said there was often a mistaken assumption that white supremacist material is hidden away on parts of the internet that are difficult to reach.