Detectives investigating the murder of a father outside a pub in Borough High Street believe he was killed in a case of mistaken identity.
35-year-old Christopher Foster was stabbed outside St Christopher's Inn shortly before midnight on Friday.
Witnesses say they saw seven suspects wearing hooded clothing carrying baseball bats and at least one knife.
A 32-year-old woman has been arrested on suspicion of assisting an offender and remains in custody.
Mr Foster, who worked at a law firm, was not married and was a father of a four-year-old girl.