A total of 10 males were wounded, two with life-threatening injuries, and two people have been arrested.
The Met said there was no information to suggest that all the incidents were linked.
A section 60 order granting police additional stop and search powers was in place across Croydon until 8am on Saturday, Detective Superintendent Nicky Arrowsmith said.
“Officers will be on patrol throughout the night across the South Area Command Unit, with additional resources from the Violent Crime Taskforce and Territorial Support Group deployed to deter and prevent any further violence.”
Police asked anyone with information that could help officers investigating these incidents to make contact.
Det Sup Arrowsmith said: “Our officers continue to work around the clock to identify and pursue offenders, bring perpetrators to justice, support victims, take weapons off the street, engage and reassure the public, and keep our communities safe in London.
“But we are not complacent and cannot do this alone. We work closely with our communities as they are key to understanding and knowing what is occurring locally.
“We need to hear from anyone who has information about crime, those who carry a weapon, or those who exploit others for gain or revenge, while putting young people’s lives at risk – we need this information to help keep London safe.”