William Li has struggled with the label hero since helping his neighbours escape the fire which engulfed the Hong Kong block of flats he had called home since birth.

Instead, he is haunted by guilt that he could have saved more people from the blaze at Wang Fuk Court, which left at least 159 people dead.

My heart breaks every time someone calls me a hero, says the 40-year-old, breaking down in tears.

A week on from the disaster, firefighters are still combing the complex of seven burnt-out high rises for the remains of 30 of Mr Li's neighbours - people who, like him, had the misfortune to be at home when the deadly fire began.

What caused the fire to start, and why more people did not escape, is now the subject of an independent committee's investigation, ordered by Hong Kong's chief executive.

Already, it has been revealed that non-fire resistant netting had been fitted around the building, and the fire alarms were not working properly.

The fact alarms did not go off was the reason why Mr Li was not more worried when his wife called to tell him a fire had started in their building, Wang Cheong House.

Instead of rushing, he spent almost 10 minutes packing belongings. But the moment he opened the door, the extent of the disaster was all too clear: he was engulfed in billowing smoke and had to retreat inside his flat.

On the other end of the phone, his wife became hysterical, but Mr Li didn't have time to panic. He had to put wet towels under the door to stop the smoke from getting in, and tried to work out what to do next.

It was then he heard voices in the corridor, where the air was now so dense with smoke he was unable to see who was calling out. Covering his face with a wet towel, he found two of his neighbours by touch, dragging the couple inside to the relative safety of his flat.

In a neighbouring block, Bai Shui Lin was also trying to help her neighbours. The 66-year-old is thought to have saved at least three families, banging on their doors to warn them of the fire. Mrs Bai did not survive, however. Her sons identified her body at the weekend.

Back in Mr Li's flat, the middle-aged couple revealed they had heard another voice in the corridor: a domestic worker calling for an elderly woman. But now, the voice had gone quiet. This time, Mr Li was unable to help.

I feel very guilty, he said. Some people weren't saved and I didn't open my door again and try to find them.

Mr Li does not know yet what happened to the voice in the corridor. Nine Indonesian and one Filipino domestic workers are reportedly among the dead, but others survived - including Rhodora Alcaraz, 28, who was trapped in another flat looking after her employer's three-month-old baby and elderly mother. She too has been hailed a hero for staying by their side.

All three were rescued by firefighters eventually - but not before Ms Alcaraz had sent a series of voice messages to her sister. I'm feeling very weak. I can't breathe, she said in one of the clips, Reuters news agency reported.

Mr Li and the couple - named in local media as the Chows - realised they too needed to escape. Several hours had elapsed, and their options were running out.

One fire exit was blocked by the flames, while Mr Li's neighbour believed the other was locked. They decided not to jump out of the second floor window due to the intensity of the fire and the constant explosions.

A subsidiary of Danish company ISS, the property manager of Wang Fuk Court, has not responded to a BBC inquiry over reports that the emergency exit was locked.

It was the first time I felt death had something to do with me, says Mr Li. That's why he started saying goodbye to friends one by one via WhatsApp: I can't escape, he told them. If something happens to me take care of my children. Look after yourselves.

About two and a half hours after the blaze began, firefighters finally reached them on an aerial ladder. Mrs Chow told HK01, a Hong Kong-based news outlet, that Mr Li insisted the firefighters should get them out first. We are older and told him he should leave first. He refused and said he was young and could handle this.

When the firefighters came back for him, Mr Li felt reluctant to leave his home, which was filled with fond memories and treasured collections of photography equipment and toys.

The fire was telling me that I couldn't take anything away, that I had no right or power to stop it from devouring everything.

Mr Li reunited with his family at a nearby fast food restaurant.

But after he'd reached hospital, it took until the early hours of the morning for the true extent of the horror he'd endured to make itself felt.

I no longer had any strength in me and when I got to the emergency room, my knees gave in. A burning smell lingered in my nose, he says. I really wanted to wash away the smell.

After being admitted to a ward at 03:00, Mr Li finally had the space to cry and start trying to process the ordeal he had gone through.

When I had been to hospital before, I wanted to go home as soon as possible, he says. But this time when the nurse asked me [if I wanted to go home], I wasn't willing to leave. I felt like I was avoiding what I would have to face in the future.

He has however decided to face the trauma upfront – by doing as many interviews as he can.

I hope many people will come forward to help find the truth, he says. I hope Wang Fuk Court residents will be given answers and justice.