Photos of smoothies are accordingly being posted on their accounts without permission. There is also a strange URL added in their biographies.
Some users are also tweeting they are being locked out on their accounts that started around 11PM ET, theverge reports.
Furthermore, other users have said photos already disappeared even before they managed to remove those. But the URL remained on place even after removing the photos.
Currently, it is recommended to keep away of clicking those mysterious links.
It is not clear what caused those hacking, but its most likely hackers have managed breached Instagrams programmed system.
Update from thenextweb: An Instagram spokesperson confirmed the incident, telling us:
Last night a small portion of our users experienced a spam incident where unwanted photos were posted from their accounts. Our security and spam team quickly took actions to secure the accounts involved, and the posted photos are being deleted.