Police investigating the fatal stabbing of a brother of two British teenagers killed fighting for Islamists in Syria have made a fresh arrest.
Abdul Deghayes, 22, from Brighton, died after being attacked in a car that crashed in the East Sussex city.
Sussex Police said on Monday that a 54-year-old man from Brighton was arrested on suspicion of murder, but warned they are still seeking others.
Chief Inspector Andy Bennett said: "We are continuing to seek a number of people who we would like to speak to in connection with Abdul's murder and I would appeal to anyone with information who has not yet spoken to us to get in touch."
A 26-year-old man who had earlier been arrested on suspicion of murder was released without charge, the force said.
The victim was found with a "number of stab wounds" in the passenger seat of a silver Volkswagen Polo just before 9.30pm on Saturday and died hours later, officers said.
Father Abubaker Deghayes said he was a "cheerful guy" who was "very popular with his friends".
Abdul Deghayes, who was jailed in 2017 for drug dealing, is the twin brother of Abdullah who was killed fighting in Syria in 2016 aged 18.
Their brother Jaffar, 17, was killed in 2014 while trying to overthrow Bashar Al-Assad's government.
The murder comes amid an ongoing international and public debate about the right of captured Islamist fighters and their supporters to return to the UK, most prominently runaway schoolgirl Shamima Begum, who has given birth to a baby boy.