A man was punched and kicked in the head after a row over a taxi in Preston city centre.
Police said that at around 5.10am on March 31, two men approached a group of people waiting to get into a taxi close to Yates in Church Street.
The men said it was their taxi but the group refused. The men then assaulted a 25-year-old man, punching him twice and kicking him in the head.
Another member of the group was also assaulted by the pair. The men then made off from the scene.
One of the suspects is described as a white male with short light hair wearing a black t-shirt, with the second man described as Asian wearing a grey hoodie.
Police are appealing for information and are urging anyone who witnessed the attack to call officers immediately.
PC Carmen Whittle, of Lancashire Police, said: “We have launched an investigation following a vicious assault in Preston city centre.
“A man has been seriously assaulted and another male attacked.
“If you witnessed either incident, please call us immediately.”
Anyone with information can contact police on 101 quoting crime reference SA1704525.