A crime scene cordon was put in place in Southend High Street on Sunday night after a man was assaulted.
The incident happened at around 5.20pm in front of a number of witnesses. Two men were reported to have been arguing outside the Greggs shop near Southchurch Road.
One of the men was struck to the head, with paramedics called to treat him at the scene before rushing him to hospital with a serious injury.
A police forensic investigator was then seen at the scene, with officers standing guard around a cordon.
A spokesperson for Essex Police said: “A 32-year-old man has been arrested on suspicion of GBH with intent and is currently in custody.
“Detectives from Southend CID are investigating whether this incident is linked to another assault in Southchurch Road at around 3.15pm which involved a fight between two men.
“We do not believe this incident poses a risk to the wider public. If you have any information, CCTV, dash cam or other footage in relation to this incident, then please get in contact with us. Please quote incident 775 of 20 August.”