Police are offering a £500 reward for information leading to the arrest of wanted man Bradley Moynes.
Moynes is sought in connection with to an attack outside Blue Bar Café in Pevensey Road, Eastbourne when an unknown substance was sprayed onto a group of people outside a bar on 11 February.
A 26-year-old man suffered serious injuries when the liquid, believed to be a noxious substance, was thrown in his face.
The investigation is ongoing and no other arrests have been made. Police say they are not seeking anybody else in connection with the incident.
Watch the moment a man throws an unknown substance over a group of people in Eastbourne
Detective Amy Summers said: “Sussex Police launched an investigation into this horrific attack as soon as it was reported on 11 February and a suspect – Bradley Moynes – was swiftly identified.
“Officers have been working with our partners in the community and neighbouring forces to urgently bring Moynes into custody for questioning, but he remains at large.
“Our greatest sympathies go out to all three victims of this unprovoked attack, one of whom suffered serious facial injuries.
“We remain in contact with the victims in order to update on any developments.''
Anyone who knows where Moynes could be or who has information about the incident is urged not to approach him but to report it online or call 101, quoting serial 1393 of 11/02.
Information can also be reported to police anonymously via the independent charity Crimestoppers on 0800 555 111.