TikTok has removed nearly two dozen accounts responsible for posting ISIS propaganda videos, The Wall Street Journal first reported. The videos reportedly presented armed ISIS militants, corpses and women proclaiming to be “jihadist and proud.”

The posts come on the heels of the U.S. troop withdrawal from Syria, a time when the so-called Islamic State may look to bolster its strength in the region.

Extremist content is the latest challenge facing TikTok, which made headlines last week after lawmakers and competitors accused the app, which is owned by Beijing-based Bytedance, of censoring content on behalf of the Chinese government. The app has exploded in popularity across the U.S. over the past few months, particularly among teens.

Read more: CNBC