Last night police dealt with a group of approximately 100 people in Brixton who caused low level disorder including throwing missiles at officers.
In order to protect the community and to ensure the highways remained clear extra officers were deployed.
Two women were arrested on suspicion of burglary after being found inside a shop in Brixton.
The shop front had been smashed.
More top news
The Metropolitan Police Federation, which set up the official JustGiving site, said it felt a "suitable amount" had been collected.
There is no evidence the Westminster attacker Khalid Masood was associated with so-called Islamic State or al Qaeda, the Met Police said.
Janet Ajao said in a statement: "I do not condone his actions nor support the beliefs he held that led to him committing this atrocity."