A 31-year-old man has been stabbed to death by two attackers on a moped in south-east London.
The victim was fatally wounded during a clash in which shots were also fired in King William Walk, Greenwich, the Metropolitan Police said.
Police were called at around 12:15am on Saturday to reports of gunshots and a person stabbed.
The assailants - one who appeared to be armed with a gun, and the other a knife - then fled the scene on the moped.
The man managed to make his way to a nearby address to ask for help, and emergency services arrived to find him with stab injuries, and he was declared dead at the scene.
Officers believe they know who the victim is, but they are waiting for formal identification and confirmation that all next of kin are aware.
Detectives have launched a murder investigation and said they "retain an open mind as to the motive".
Detective Inspector Jo Sidaway, who is leading the investigation, said: "At this early stage, it is understood the victim was approached on King William Walk by two suspects on a moped.
"One suspect is believed to have been in possession of what appeared to be a firearm, the other a knife.
"During an altercation between the suspects and the victim, the victim was stabbed. The suspected firearm was discharged, but enquiries continue regarding this.
"The suspects then fled the scene on the moped, and the victim then managed to make his way to a nearby address to ask for help. He was later pronounced dead there.
"I am appealing for any witnesses to any part of the incident, or anyone with any information, to contact our incident room and assist our investigation."
A post-mortem examination is expected to take place later on Saturday.
Anyone with information is urged to call police via 101 or call Crimestoppers on 0800 555 111.
The killing is the latest harrowing crime to hit the capital in which the perpetrators were riding a moped.
On Thursday night, a string of acid attacks were allegedly carried out by two men driving a scooter.
Their mode of transport allowed them to inflict five attacks on fellow moped drivers in a 90-minute window across north and east London.
Two teenagers, aged 15 and 16, were arrested on suspicion of grievous bodily harm and robbery.
They remain in police custody.