Suffolk police attended an address on the Ipswich Waterfront as part of a murder probe following the death of a 21-year-old man in Clacton.
A spokesman for Suffolk police confirmed that officers were called to a property in Key Street on Wednesday, September 15, to assist Essex Police in their murder inquiry.
An eyewitness said they saw a large police presence in the area with five police cars and two forensic vans.
Harry Burkett, died after suffering a stab wound in Orwell Road on Sunday, September 12.
Officers were called to the scene shortly after midnight to reports a man had been injured.
On arrival police found the 21-year-old man had suffered a stab wound.
Mr Burkett was treated at the scene by paramedics but died at hospital.
On Wednesday evening Essex Police arrested a 16-year-old boy from Clacton on suspicion of murder and a 18-year-old woman from Clacton on suspicion of assisting an offender.
Both remain in custody at this time.
An 18-year-old man and a 17-year-old girl, who were arrested on suspicion of murder, have been released on bail until October 7.
A 20-year-old woman arrested on suspicion of assisting an offender has also been released on bail until October 7.
Essex Police have been approached for a comment.
Anyone with information that could help officers in their investigation is urged to contact Essex Police, quoting incident number 5 of September 12.
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