Southport robbery victim suffered liquid face burns
A 49-year-old man suffered burns to his face and eyes after a group threw an unknown liquid over him and stole his mobile phone and wallet.
Merseyside Police said "three males and a female" aged 17-19 also punched and kicked the man on Hawkshead Street, Southport at 21:35 BST on Saturday.
The man is being treated in hospital where his condition is "stable".
A police spokesman said tests were taking place to identify the substance that was thrown on the man.
Det Insp Simon Vaughan said: "This was a shocking and completely unprovoked attack on a man who was simply walking home.
"Violent robberies such as this will not be tolerated by Merseyside Police and I am sure the local community will agree this is completely unacceptable."