The same day Gen. Qassem Soleimani’s funeral procession filled the streets of Ahvaz, Iran, thousands of pro-Iran Instagram accounts worked in coordination to tag the US president’s family in image posts ranging from the Iranian flag to a beheaded Donald Trump.

The Instagram accounts for Ivanka and Melania Trump were the primary focus of the campaign, but those belonging to Donald Trump Jr., Lara Trump, and the @Trump company handle were also tagged in some of the close to 30,000 posts identified in a BuzzFeed News analysis. One of the most active accounts tagged Ivanka Trump in pro-Iran posts nearly 250 times in less than 24 hours.

“The campaign you highlighted is essentially a digital ‘flex’ or effort to intimidate,” Cindy Otis, a former CIA officer and the author of True or False: A CIA Analyst’s Guide to Spotting Fake News, told BuzzFeed News.

Many of the posts featured Iranian flags and images of Soleimani and used a Persian hashtag that translates as “hard revenge.” Other posts were more threatening, featuring coffins wrapped in the US flag, images of a beheaded President Trump, or a T-shaped hand symbol with the words “US officers who came vertically will return horizontally,” echoing the words of Hassan Nasrallah, the leader of Hezbollah. He said US forces would leave the region “in coffins.”

BuzzFeed News gathered data on more than 28,000 images and videos that tagged at least one of those five Trump family accounts in recent days. The data spiked on Sunday, Jan. 5, the day of the funeral procession for the slain head of the Quds Force. The sharp increase and decrease in activity suggests it was a coordinated harassment campaign.

“Tagging public figures on Instagram is not unusual during major global events,” a Facebook spokesperson said. “We will take appropriate action if we find any content that violates our community guidelines, US sanctions law, or is the product of inauthentic behavior.”

Facebook’s community guidelines on harassment say the company will “remove attacks that are severe as well as certain attacks where the public figure is directly tagged in the post or comment.”

For its analysis, BuzzFeed News focused on posts uploaded between Jan. 5 and mid-afternoon the next day, the time frame around Soleimani’s funeral. Most of those 28,000 posts — about 70% — came from users who tagged Trump family members in just one post during the time period. Another 25% came from users who tagged the accounts in two to ten posts.

Two of the most prolific accounts in the dataset did not list a name or other identifying information and exclusively shared content that tagged the Trump accounts. One account, f.mousavi1379, shared 87 images that were tagged with Trump handles. The second account, arebelwithahalo, shared 247 images — all of which tagged Ivanka Trump.

“Since the strike last week, the Iranians have made a show of using a full-spectrum response, from the missile strikes last night to cyberattacks and attempts to manipulate international perception of their capabilities through information operations,” Otis said.

Facebook, Twitter, and Telegram are censored in Iran, but Instagram is still available. According to an analysis by Mahsa Alimardani, who researches social media use in Iran with the Oxford Internet Institute, “hard revenge” was among the top-trending hashtags for social media posts in the country in the days following the drone strike that killed Soleimani.

The onslaught of tagged photos isn’t the only sign of coordinated activity on Instagram. Karan Kanishk, a researcher with the Atlantic Council’s Digital Forensic Research Lab, noticed a series of pro-Iran posts on Instagram and Twitter that tagged the White House as their location on the day Soleimani was killed. “Prepare the coffins,” the images said. One of the accounts that posted the images previously sold sneakers. That account is still online.