A woman was left with burns after an "unknown substance" was thrown on her at a pub.
Hampshire and Isle of Wight Constabulary said the 52-year-old woman was doused with the substance at The Golden Lion on Jay's Close.
As she walked through the pub, a substance was thrown on her hair and back. She suffered reddening to her skin and blisters, and had to have most of her hair cut off.
The force said she had been left "extremely distressed" by the incident, which took place at the Basingstoke pub between 9.30pm and 10pm on 10 February.
The Constabulary added that work was ongoing to establish what the substance was, but it is not thought to be acid.
Two men, aged 48 and 53, both from Basingstoke, have been arrested on suspicion of attempted grievous bodily harm with intent.
Witnesses can provide information by calling 101 and quoting 44240061292, or by visiting the Hampshire Constabulary website.
The charity Acid Survivors Trust International said that according to freedom of information requests, police in England and Wales recorded 710 corrosive substance attacks in 2022.
The figures marked a 69% increase from 2021, which saw 421.
It comes after a man had a noxious substance thrown at him in a graveyard in Ramsgate, Kent, on Sunday.
He was taken to a local hospital, where he was treated for burns to the back of his head. His injuries were described by Kent Police as non-life threatening.