The U.S. Department of Defence put out a rather on-the-nose tweet about recognizing the signs of mental illness on social media Monday, triggering a wave of snide remarks that the message was aimed at U.S. President Donald Trump.

"Social media postings sometimes provide an important window into a person's mental health," the DoD tweeted. "Know what to look for."

Social media postings sometimes provide an important window into a person’s #mentalhealth. Know what to look for. https://t.co/B0tPAHwjVK pic.twitter.com/AbXrw2QhQd — U.S. Dept of Defense (@DeptofDefense) January 23, 2017

The link leads to a page offering advice on using social media to help loved ones dealing with mental illness.

The seemingly innocuous tweet nevertheless set off a wave of ridicule for Donald Trump, the notoriously thin-skinned and boastful U.S. president.

I just tripped over in the gloom because of the ALMIGHTY SHADE being thrown out by this tweet. https://t.co/HZOkZyv0s5 — Leilah Skelton (@Leilah_Makes) January 23, 2017

@DeptofDefense have you look at the posts by your Commander in Chief? @potus needs immediate help. — Liberal Venom (@LiberalVenom) January 23, 2017

@DeptofDefense me reading this knowing it's the ill Trump subtweet. pic.twitter.com/SsS3iAdVxm — Erick Fernandez (@ErickFernandez) January 23, 2017

@katherineshelby @DeptofDefense important thing is it'll be up long enough to make a YUGE impact. — TBashII (@RukhnamaLives) January 23, 2017

Trump has frequently used Twitter to lash out at his critics in politics, business, the media, entertainment and the world at large. On Sunday, for instance, he criticized the Women's March on D.C. "Why didn't these people vote?" he tweeted. "Celebs hurt cause badly."

He also uses the social media platform to boast about his accomplishments, whether or not they are verifiably true.