Multiple schools in Paraguay received threats of violence, with messages found written on bathroom walls. Authorities are investigating the potential source, including rumors of a viral online 'challenge'.

<p> <img alt="The phenomenon extends beyond Paraguay. In Argentina, threats with nearly identical messages &mdash; &#147;Tomorrow, shooting. Don&#039;t come&#148; &mdash; appeared in at least a dozen schools across Buenos Aires" height="80" src="https://en.mercopress.com/data/cache/noticias/109839/100x80/pys.jpg" style="float: left; margin: 0 12px 6px 0; border: 1px solid #333;" width="100" /> At least 12 schools in Paraguay received shooting threats between Thursday and Fri...