The sister of a soldier who could be in line for a Victoria Cross claims she has been left in the dark about her brother's heroics.

While the rest of the country has read about the courageous actions of Private Johnson Beharry in the national press, his sister in Selhurst says she has met a wall of silence in her attempts to find out what really happened to him.

Pt Beharry, who is being treated in a military hospital in Birmingham, awoke from a two-week coma last week amid calls for him to receive the highest military honour for gallantry, the Victoria Cross, last awarded 22 years ago.

The 24-year-old, who lived in West Croydon for four months with his sister before joining the army, is reported to have risked his own life to save 30 comrades from two terrifying ambushes in Iraq.

His first heroic display is thought to have happened in May when he led a convoy of troop carriers safely through an ambush despite his vehicle being on fire and having a bullet lodged in his helmet. He then went back to the burning vehicle and pulled his commander from the flames while under heavy gunfire.

It has also been reported that three weeks ago, in a second ambush, a rocket grenade exploded close to his face but Pt Beharry managed to manoeuvre the carrier to safety before passing out. His actions saved the lives of the crew and his commander for a second time.

Jacki Beharry, a 28-year-old student, told the Guardian she knew nothing of his bravery until last week when she was approached by newspapers and television crews.

She said: "We just don't know anything. All we were told a few weeks ago was that Johnson had been in a tank explosion and that he had head injuries. The MoD has told us nothing and neither has Johnson. Even if I ask him he won't be allowed to speak of what happened to him, that's the policy in the armed forces.

"I've been stunned to read of what he did. I couldn't believe it when I picked up the paper and saw my brother on the front.

"The information is so detailed that it must have come from a military source, but I'm not surprised. It's the sort of thing he would do.

"He is being very modest. He keeps saying it was his duty. I am just so thankful he is still with us."

Married Pt Beharry, who now lives in Southampton, was in a coma for two weeks in a Kuwaiti hospital but was transferred to the UK last week after he regained consciousness.

Jacki, whose family is originally from the Caribbean island of Grenada, travelled to Birmingham at the weekend to see her brother was joined by their mother. She added: "He's fine in himself. He's been complaining about the hospital food so we know he isn't brain-damaged.

"We've been told it may take up to a year of rehab to make him physically well, though."

An MoD spokesman was unable to comment as the Guardian went to press.