The Selective Service System—that maintains information on those potentially subject to military conscription in the US—website crashed Friday because of "the spread of misinformation," the agency tweeted, CNN reported.

The website's crash came hours after the announcement that the head of Iran's Revolutionary Guards' Quds Force, Qasem Soleimani, was killed by a US airstrike ordered by President Donald Trump. The hashtag #WorldWarIII was one of the top trends on Twitter Friday.

The incident led to threats of retaliation from Iran's government and the escalation of tensions between the US and Iran. It sparked fears on social media of a war between the two countries and the possibility of another military draft in the US.