Open displays of support for the Islamic regime in Iran were seen throughout Sunday's Arbaeen Procession in London.

The Arbaeen Procession is an annual public march held to commemorate Imam Hussain, the grandson of the Prophet Muhammad, who was martyred in Karbala, Iraq, in 680 CE.

Arbaeen marks the 40th day after his martyrdom and is designed to remember his believed stand against oppression and injustice. For those who cannot get to Iraq for the Karbala procession, there are many similar marches around the world.

Sunday's Marble Arch procession, organized by Hussaini Islamic Trust UK, saw an estimated 35,000 people attend. According to the trust, this was the largest-ever gathering in the 46 years the event has been held in the UK.

While the entire purpose of the event is to remember and commemorate Hussaini's stand against injustice and oppression, Sunday's event saw significant support for Islamic regime figures.