Castle Street in the city center remained cordoned off by police this morning.
Police told ECHO they were called to the scene at around 9:28 p.m. on Saturday 24 October.
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Police said a 30-year-old man was taken to Aintree hospital with head injuries following an assault.
It remains in critical condition.
What appears to be rags or bloody clothing can be seen at the scene of the police cordon on Castle Street.
Merseyside Police said an investigation was underway.
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