By Dominic Casciani BBC News Online community affairs reporter

Today and every day the Koran requires this of all Muslims worldwide.

And in the serene surroundings of London's Central Mosque a small gathering of leading Muslims called on fellow Britons to join them in seeking hope for all of humanity in the wreckage of 11 September.

This is a very important day for us because we will remember for the rest of our lives those people, who for no crime of their own, lost their lives

Ajmal Masroor

The ceremony, organised by the Islamic Society of Britain (ISB), was a small affair compared to that which would be taking place a short time later at St Paul's Cathedral.

But those who spoke at the mosque sought to do so for the UK's two million Muslims who have found their faith and way of life under siege for the past year.

Ajmal Masroor of the ISB told the audience that one of the lessons of 11 September should be that we are "human first, and that is something that unites us".

He said that Muslims throughout the world had condemned the destruction of 11 September from the very first day because it went against everything that their faith required of them.

Joe Ahmed-Dobson: "Choose the Straight Path"

"My message is of a balanced, tolerant and peaceful view of Islam. This is a very important day for us because we will remember for the rest of our lives those people, who for no crime of their own, lost their lives."

Mr Masroor said that on this day last year he had sat numb as he watched the events unfold. Within minutes he and other leading Muslims were already discussing how they would distance their faith from what had happened.

"The memory of the day is still fresh. When I see pictures of the Twin Towers these memories return to my mind and it pains me greatly."

One of the key speakers at the event was Joe Ahmed-Dobson, a prominent British convert and the son of Labour former cabinet minister Frank Dobson.

'Offensive' attribution

Mr Ahmed-Dobson said that the past year had demonstrated that all nations and faiths must actively work for peace.

Ajmal Masroor: "Balanced, tolerant view of Islam"

"The world is well aware that those who carried out the attacks attribute their actions to Islam itself.

"This attribution was and continues to be grossly offensive to the overwhelming majority of two million Muslims in the UK and one billion across the globe.

"Throughout the ages men have falsely attributed violence and intolerant actions to their faith. The vast majority of Muslims and those of all religious faiths hold their beliefs dear and choose what in Islam we would describe as 'the straight path of good, peace and justice'."

Mr Ahmed-Dobson said that the Koran made clear that "whoever kills a human being shall be regarded as having killed all mankind".

Among those killed in the Twin Towers were an estimated 70 Muslims. One of those was Briton Sarah Ali.

Her mother had planned to speak at the event, but as the morning of 11 September dawned she found the burden too much to bear.

That's the most important thing to remember - that they are a Muslim family who have also lost a loved one

Sarah Joseph

Sarah Joseph, a friend of the family, spoke in her place.

She said: "I do not come here able to represent the Ali's because theirs is a pain and private grief which is inconsolable."

"They are an ordinary Muslim family and when I think of Auntie [Sarah Ali's mother], I see a humble, religious woman who loved her daughter.

"That's the most important thing to remember - that they are a Muslim family who have also lost a loved one."

Today there is sorrow throughout the Muslim community in Britain and abroad. It is a sorrow under a dark cloud of fear for their own security in the UK, and fear for their brothers and sisters facing conflict elsewhere.

As the ceremony ended, the gathering sought solace in a saying of the Prophet Muhammad: "The throne of God shakes when the cries of the orphans and oppressed are heard."