A second Iranian protester has set herself on fire outside the French Embassy in London.
Heshmat Zandi doused himself with petrol outside the embassy
A 25-year-old woman is critically ill at the Chelsea and Westminster Hospital after police found her outside the French Embassy in Knightsbridge at 1915 BST.
On Tuesday engineering student Heshmat Zandi, 38, suffered 40% burns after dousing himself in petrol.
Demonstrators gathered outside the embassy in protest at the arrests of 150 members of the Iranian opposition group the People's Mujahideen in Paris.
French intelligence accused the People's Mujahideen, an armed opposition group, of planning terrorist attacks at embassies across Europe.
Laila Jazayeri, of the Iranians in London Association, said the woman was called Neda Hassani, aged 25, and an Iranian living in Canada who was on holiday in the UK.
She said: "She has always supported the People's Mujahideen of Iran, she has been struggling to achieve freedom and democracy in her home land.
"When she heard the news yesterday, I saw her among the demonstrators and she was really angry."
While Mr Zandi's protest took place in front of up to 60 demonstrators, Ms Hassani set herself alight after Wednesday's protest had finished.
A Scotland Yard spokesman said police were maintaining a presence outside the French Embassy.
A further three Iranian protesters set themselves alight outside France's domestic intelligence service on Wednesday, where scores of protesters gathered.