Press TV- Millions of Muslims in Iran and across the world are observing the passing anniversary of Islam�s holy Prophet Muhammad (Peace be upon him).

The 28th day of the month of Safar (the second month in the lunar calendar) marks the passing away of Prophet Muhammad�as well as the martyrdom of his grandson Imam Hassan (PBUH), the second Shia Imam.

Large groups of Iranians, along with Muslim pilgrims from other countries, have gathered in the northeastern city of Mashhad to take part in the mourning ceremonies at the holy shrine of Imam Reza, the eighth Shia Imam.

The cities of Qom and Shiraz, which are home to shrines of revered Shia figures, are also hosting large gatherings of mourners marking the tragic events.

People in other Muslim countries also commemorate the Prophet of Islam�s passing by holding special mourning ceremonies.

Prophet Muhammad�(PBUH) was born in about 570 AD in the Saudi Arabian city of Mecca. He was granted to be the final prophet by Allah at the age of 40. He passed away at the age of 63 after 23 years of disseminating the message of Islam.

Safar also saw the martyrdom of Imam Reza. Mourners are set to mark the sad anniversary on the last day of the lunar month, which falls on November 30 this year.