MURMANSK – Valentina Avelene never wanted her son to go into the Navy. When Sergei got his call-up papers for compulsory military service last fall, she begged him not to go and tried to persuade him to hide at his grandmother's house for a few months to escape conscription.

But Sergei Vitchenko, 20, was determined to serve his country and refused to listen to his mom's entreaties. He was delighted when he was dispatched to take part in perhaps the most prestigious mission possible within the Russian Navy, serving on the country's most sophisticated nuclear submarine cruiser, the Kursk.

The conscript Vitchenko was the lowest ranking member of the crew and struggled to be promoted to the position of junior cook. He took pride in his work, and his letters home expressed enthusiasm for his new life.

As Avelene made her way to join the relatives' vigil within the closed military town of Vidyayevo – the headquarters of the Kursk command – she gripped two letters that could be the last words to come out of the doomed submarine – a letter from her son and another from the captain. Sergei's letter arrived at her home in a small country town in Lithuania on the day the Kursk went down.

• A young submariner

The letter, written on four sheets torn out from a child's lined exercise book, gives the impressions of a young submariner experiencing conditions on board a nuclear cruiser.

For almost a week after the vessel sank, Avelene was too worried to sleep or do anything except stare at the television, waiting for news. But despite her profound exhaustion, the act of reading aloud her son's last words gave her momentary release from her anguish – prompting her first to smile and then to laugh. Last Sunday, when she met with this reporter, she still held out hope that he was alive.

"Dear Mama and Papa Thomas," Sergei began the letter to his mother and his stepfather. "I have received all your letters. I'm sorry I haven't written for such a long time. ... We were at sea but now we are sitting in the port, loading up rockets. ... "

Sergei described his pride at having earned his colors as a true submariner, after his first descent with the Kursk to the bottom of the sea.

Apologizing for her son's poor handwriting, grammatical errors and use of Russian slang, Avelene, 43, read on: "We were baptized as submariners – we were called to the command post where everybody drank a cup of seawater and kissed a greased ship's hammer – then we got these papers and the commander shook everyone's hand. But after drinking the seawater, we all felt a bit sick."

He told his mother his next trip to sea would be over by the end of August, when he would return to land – and promised to take some pictures of the scenery for her, so she would get an idea of his surroundings. The letter, written July 23 – just before the submarine embarked on its final journey – ends with another proud reference to his new job: "`Bye, I love you. I miss you. Write to me, Seryozha (a cook)."

Carefully folded alongside this letter, Avelene has also preserved a letter she received from the submarine's captain, Gennady Lyachin, in May, informing her that her son was serving on the Kursk and praising his progress.

• Chilling reminder

This, too, is handwritten on cheap, rough brown paper. The absence of a typewriter, let alone a computer, is a chilling reminder of the low-tech world in which the captain of one of Russia's most advanced submarines was working.

"The command informs you that your son, sailor Vitchenko Sergei Alexandrovich, is currently serving in the Russian military Navy on the nuclear missile submarine Kursk, one of the most modern, battle-capable vessels not only of Russia but of the whole world," the captain wrote.

Avelene proudly read on: "Your son, sailor Vitchenko, has started to grasp his job ... with interest and dedication. ... I am certain that for the rest of his life your son will bear the highly respected badge of a Russian submariner with pride, dignity and honor."

The letter was signed: "With my best wishes, commander of the nuclear submarine cruiser, Kursk, Capt. G. Lyachin."

Avelene, a construction worker, arrived in Murmansk last Saturday after colleagues at the construction firm where she works collected the money to pay for her plane ticket. She had been unable to afford the fare, and the Russian military had offered no financial support. She was waiting at the railway station for her daughter to arrive from St. Petersburg; naval officials were then to take them to join the 208 other Kursk relatives gathered in Vidyayevo – among them 49 wives, seven fiancees, 42 mothers, 11 brothers, 16 sisters and 39 children.

Avelene held a deeply felt bitterness at the response of the Russian government and military to the crisis.

She was horrified by the Kremlin's initial refusal of foreign assistance in the rescue effort. "I'd like to see [President Vladimir] Putin put in a boat and sent to the bottom of the sea – to experience what they went through," she said, overcome with anger. "People get punished when they betray their country. But what if a country betrays its people?"

• News heard on radio

She was also dismayed by the lack of support from the military. Her family heard the news of the sinking on the radio late Sunday evening; early Monday they sent a telegram to the naval headquarters trying to establish if Sergei had been on board.

They received no answer. Avelene spent hours trying to get through to an emergency hotline, but failed because the number was always engaged. Finally, she saw her son's name listed on television as one of the trapped men. No official had made any attempt to contact her.

Text of the son's letter:

Dear Mama and Papa Thomas,

I have received all your letters. I'm sorry I haven't written for such a long time and that I am replying so late. We were at sea and now we are sitting in the port, loading up rockets. When we have done this we will go out to sea again, and then we will return to Severomorsk for the military parade. Tomorrow I will try to send this letter.

Everything is fine with me; they finally accepted me to work in the ship's mess, and so now I'm working as a cook and not in the cargo room.

I have just hurried to prepare lunch so now I've got a free hour. The cooks are a privileged class on the ship – we are allowed to wash every day and we get to sleep for 12 hours a night. Tell me what the commander's letter said – what did he write about? I'm interested to know. ...

Congratulations on passing your driving test. So can you really drive a car now? To be honest, Mama, I can't imagine you in the driver's seat. I can't wait for you to send me a picture of you behind the wheel.

When we arrive back at base, I will write to everyone. But I think we will be at sea until the end of August.

I have been awarded my submariner certificate. We were down at about 100 meters, but that's by no means the deepest our boat can go – even 480 meters is no problem. Later I'll try somehow to send this certificate home for you to keep as a souvenir.

We were baptized as submariners – we were called to the command post where everybody drank a cup of seawater and kissed a greased ship's hammer – and then we got these papers and the commander shook everyone's hands. But after drinking the seawater, we all felt a bit sick.

When we come back from the sea I will take some photos, and then you can see where I have been serving.

Well, I have probably already begun to bore you all with my letter, so I'll stop.

Bye, I love you. I miss you. Write to me, Seryozha (a cook).