Police were called to Coldharbour Lane at 01:14 BST on Saturday, where three others aged 21, 47 and 70 were also shot and taken to hospital.
The Metropolitan Police said their injuries were not life-threatening or life-changing, and no arrests had been made by Tuesday morning.
Detective Chief Inspector Allam Bhangoo called it a shocking act of violence and appealed for witnesses or footage as officers work to identify those responsible.
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