A 36-year-old woman has been arrested on suspicion of incitement to murder following the death of Grimsby man Tony Richardson on Monday.
Tony, known as Tosh, died in hospital on Tuesday following the attack in Old Market Place in the town.
A 44-year-old man remains in custody on suspicion of murder.
Both people arrested are from the Grimsby area.
Humberside Police are now appealing to find a jacket connected with the investigation.
The jacket is believed to have been discarded in the Worcester Avenue/Winchester Avenue of Grimsby since Tuesday afternoon.
It is described as a ‘dirty’ light grey Lyle and Scott hooded jacket.
Anyone who has seen this jacket or knows where it is should call the incident room on 01472 290204.
Detective Chief Inspector Stewart Miller said: “I want to re-iterate that the attack on Tony was an isolated incident targeted towards him and not the wider community. We continue to have a community police presence in the town centre to offer reassurance to the residents and businesses locally.
“We are very grateful to the public for their assistance thus far and would encourage them to continue to provide us with any information that could be relevant to Tony’s death.”