Lollapalooza organisers have launched an investigation into allegations British singer Dev Hynes was assaulted by security guards at the Chicago, Illinois festival on Friday (01Aug14).

The Blood Orange star claims he and his girlfriend, Samantha Urbani, were "jumped by three security guards" after his band's late afternoon performance and he is planning to press charges over the incident.

He has also taken aim at event officials for reportedly deleting fans' references to the alleged altercation from their social media sites and claims one of the bodyguards involved is now accusing Hynes of assaulting him, instead.

Taking to Twitter.com, the singer writes, "Apparently people are tweeting & writing on @lollapalooza Facebook page (sic) and they keep deleting the comments."

He continues, "Ps. One of the security guards is claiming that I assaulted him which is insanity. If you saw the incident please get in touch. Thanks."

Organisers have since vowed to get to the bottom of the alleged incident.

In a statement issued to Pitchfork.com, they write, "Late Friday night, we learned of an incident involving an artist and a security guard on site. Since then, we have been in contact with those involved and the authorities, as we work together to resolve the situation. As always, our top priority is to ensure the safety of everyone at the festival."