Sarah Rainsford BBC correspondent in Moscow

Addressing a small crowd huddled on the Moscow roadside, Admiral Viktor Kravchenko opened a modest ceremony to commemorate the worst naval disaster in Russia's peacetime history.

"Two years have passed since the icy waters of the Barents Sea stole the lives of 118 crew members aboard the Kursk," the navy's chief-of-staff said.

This memorial is good, but the main memorial is in our souls

victim's father

"On that day, one of Russia's finest crews died. The sailors fulfilled their duty to the end. Their courage and heroism are a shining example of selfless service"

A military band played the national anthem as the cloth was pulled from the new memorial: a five-metre high bronze sailor, cap in hand and eyes downcast, standing before a miniature model of the Kursk.

The plaque beneath reads simply: in memory of those who died.

Following a naval delegation, relatives and friends of the dead passed slowly in front of the statue to lay single red roses and carnations at its feet.

They were accompanied by war veterans, their chests heavy with medals, and serving naval officers.

Putin absent

Some had expected Russian President Vladimir Putin to put in an appearance, but in the end it was a low-key event.

The president, who was heavily criticised two years ago for his tardy response to the tragedy, carried on Kremlin business as usual.

The Moscow ceremony was echoed in cemeteries and churches around Russia as groups in St Petersburg, Kursk and Vidyayevo - the submarine's naval base town - marked the anniversary.

Many relatives are not satisfied with the official inquiry

Kirill Belyaev's father was a senior chef on the Kursk. Like many in the small crowd, he remembered him with tears.

"This memorial is good, but the main memorial is in our souls" Kirill said.

"Every year summer, autumn and winter pass, and you start to forget. Then these anniversaries come around, and all the memories swim up again. It's really tough, emotionally, on all of the relatives"

Mystery remains

But like many relatives of the crew, Kirill does not believe he and his family will ever know what really happened to send the mighty Kursk plummeting to the bottom of the sea.

"I think it wasn't quite how they tell us" he said "But no one will ever tell us the truth."

An official investigation recently concluded that a faulty torpedo triggered a chain of fatal explosions on board, and the courts have found no-one to blame.

This month the final fragments of the submarine will be destroyed on the sea bed.

But for the families marking their loss today, the questions and doubts still remain.