A London woman arrested in Iran for watching a men's volleyball match has gone on hunger strike in jail.

Ghoncheh Ghavami, who has dual British Iranian citizenship, has been held in jail in Tehran for three months.

More than half a million people have now signed a petition demanding her release.

Home Affairs Correspondent Guy Smith talks to Ms Ghavami's brother Iman and Raha Bahreini from Amnesty International UK.