Police are continuing their enquiries into the death of a man in Laindon on Sunday evening.
The man, aged in his 30s, was found stabbed in Iris Mews shortly after 9.30pm on May 2.
Overnight, officers made another arrest. In total, five teenagers have now been arrested on suspicion of murder. All remain in custody.
Detectives have been working to establish what happened in the moments leading up to the attack.
Detective Chief Superintendent Steve Jennings, of the Kent and Essex Serious Crime Directorate, said: “Our enquiries have led us to believe the victim was going to the aid of another man and, as a result, he lost his life during an altercation which ensued with a group of young people not directly known to him.
“It is a tragic loss of life and we are continuing to appeal for the public’s help.
“We are really keen to hear from anyone who was in the area at the time and may have seen or heard anything happen in Iris Mews shortly before 9.30pm on Sunday.
“We are also keen to hear from anyone who has seen any discarded weapons in the area.
Anyone who witnessed the incident, has footage of what led to it or has information on it should submit a report online at https://www.essex.police.uk or use the ‘Live Chat’ button to speak to an online operator between 7am-11pm.
You can also call 101 and cite incident 1292 of May 2.
Information can also be given to independent charity Crimestoppers anonymously on 0800 555 111 or https://crimestoppers-uk.org.