Police found a machete in a Dagenham street on Saturday while at the scene of a suspected stabbing.
Officers were called to reports of a fight at the Heathway junction with Church Elm Lane shortly after 6.30pm.
The Met attended along with paramedics from London Ambulance Service.
They found the weapon but no victim or suspect.
Officers treated the scene as a suspected stabbing and set up a cordon in the road.
“There is a crime scene in place, so please avoid the area,” said the Met’s Barking and Dagenham Police Twitter account.
“We’re are [sic] appealing for witnesses to the incident to contact 101 urgently.”
The incident came nine days after Abdulrahman Nassor Juma, known to friends as Mani, was knifed to death in Barking.
The 23-year-old was pronounced dead at the scene in Crows Road.
A 22-year-old man arrested on suspicion of Abdulrahman’s murder has been released on bail.
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