The Barnardo’s shop in Brixton had its window smashed after crowds gathered to "celebrate" the death of Baroness Thatcher yesterday.
The children’s charity said the shop has been forced to close while the premises were made safe after the incident last night.
Police were called to the so-called "Thatcher death party" in Brixton, one of several held around the country, which were organised on Twitter and Facebook after it emerged that the former Prime Minister had died at the Ritz Hotel in London as the result of a stroke.
A spokeswoman for Barnardo’s said: "The Barnardo’s store in Brixton was damaged during the evening of 8 April and has been forced to close while the premises are made safe.
"We apologise to all our customers for the temporary closure and will ensure the store is re-opened as soon as possible.
"The incident has been referred to the police and we are assisting them with their inquiries."
Police said officers dealt with about 100 people in Brixton who were causing low-level disorder last night.
Brixton was the scene of two riots during Thatcher’s reign as prime minister.
News of Thatcher’s death was met with cheering and applause at the annual conference of the charity the National Union of Students in Sheffield.
Liam Burns, president of the NUS, took to the stage and said: "I’m the last person to agree with Margaret Thatcher’s politics or her policy record as Prime Minister. But we must not forget that an elderly woman has just died. She had family, friends, colleagues and supporters who will want to pay their respects at this time, and the media and public debate will now be dominated by this unexpected news."
Other students took to Twitter to condemn the response, labelling it "disrespectful" and "immature".