On April 4, a suspected chemical attack on the rebel-held town of Khan Sheikhoun in Idlib province left 91 people dead and at least 557 wounded.

Among the dead were at least 29 internally displaced Syrians, according to the Syrian civil defence group the White Helmets.

Some of the victims were as young as nine months old.

"Can you imagine waking up early in the morning and seeing your children, convulsing, foaming and unable to breathe," said Zaher Sahloul, a Syrian-American doctor, in an interview over the phone.

"It [the gas] affects your breathing muscles. You are completely alert but unable to breathe in or out. That's why this is the worst type of death," explains Sahloul, who still remembers pictures of the first chemical attack on his home city of Homs in 2012.

The Khan Sheikhoun attack was yet another bloody chapter of the conflict in which Syrian civilians have been targeted with barrel bombs, phosphorous bombs, cluster munitions, bunker busters, chlorine, mustard gas and nerve agents, all intended for maximum casualties.

The Syrian American Medical Society, based in Washington DC, where Sahloul works, has documented at least 175 cases of chemical attacks since the beginning of the war in 2011.

"Any monster who justifies that and any monster who defends the person who uses it [poisonous gas] doesn't deserve to be called a leader in this world," Sahloul says.

Last Monday, a Human Rights Watch report blamed the Assad regime of using nerve agents on at least four occasions since December 2016, the deadliest attack being in Khan Sheikhoun. Syrian opposition groups and activists also blamed the sarin gas attack on the regime of President Bashar al-Assad. Although the Syrian military has rejected the accusations, Western governments hold the Assad government responsible for the deadly attack.

Survivors of the attack say many of them knew that the death of their loved ones in the course of the war that ravaged their country was a real possibility but no one thought it would come this way.

Al Jazeera spoke to some of the survivors who shared their stories of sorrow and helplessness.

Displaced and bombed

Jamal Al Qasem, 57

We arrived in Khan Sheikhoun three years ago from Mourik in Hama province. There was nothing left in my town, where most houses were destroyed by incessant bombings, and almost everyone had left. The regime was constantly bombing us and the frontline in Hama was slowly getting closer. One day, I decided, we had to leave. We carried nothing with us except a dim hope for our safety.

Since we arrived in Khan Sheikhoun, we have been at the mercy of strangers, living on charity. Last year, during Ramadan, someone told me that it’s safe to go back because the rebels had captured the city. When we returned, we found our home destroyed due to the fighting. But I was happy to be there. I tried to clear the dust and debris of one room where the bricks were still tethered together to live with my family.

It was my house, after all, in my city where I was born, close to our family's pistachio farms where I spent my happiest days working and playing with my children. It didn't matter that the regime had destroyed everything in the city, including the drinking taps. We were at home.

Our relief, however, was short-lived. We could only spend 20 days there till the regime started bombing us again, and we were displaced one more time.

We returned to Khan Sheikhoun, where strangers opened their doors to us yet again, but our neighbourhood was under constant attack. We kept moving from one neighbourhood to the other for safety.

Last month, I decided to go to a refugee camp close to the Turkish border, but it didn't have enough tents. So I left my son, his family and my daughter back in Khan Sheikhoun till I could find somewhere safe for them to stay. But no place is safe in Syria.

It was 8:30 in the morning on April 4. My neighbour called to say there was an attack right outside where my family lived. He told me this attack was different from others. I jumped into my car and drove for 120km back to Khan Sheikhoun.

There was chaos in the hospitals. Heaps of clothes were piled on the floors. Everyone was naked, lying on the floor. Their bodies were wet from the sprinkling of water in the wake of the gas attack. The dead were stacked in the hallway along with the injured, who looked like they were dead, with pale skin and red eyes. As I raced from one hospital to the other; the hope to see my children alive was slowly fading.

When I first saw their bodies, I thought someone had poisoned them. Thick foam was coming out of their nostrils and mouths. I lost my daughter, my son, his wife, and my sister.

My daughter, Fatima, was only 15.

I worked for the government for 27 years till I retired in 2005. I support the Syrian revolution because I was tired of the police state. I have never carried a gun in my life.

I have heard what they have been saying about these attacks. We are used to the lies of the regime and Russia by now. I think they lie to help themselves sleep at night.

The yellow mist

Kusai Al Yousef, 34

It was early in the morning. I was asleep with my wife and three children when suddenly I heard the sound of jet followed by a loud bang which woke me up. I thought it was just another air strike. I quickly asked my family to run towards the basement and rushed out to help others.

When I reached the neighbourhood, I was surrounded by a yellow mist. My nose started to bleed. I keep vomiting, even now, and have trouble breathing.

We are used to the bombings but no one expected this. There was panic everywhere, no one knew what to do. Everyone was gasping for breath.

I saw a small child foaming from his mouth. I scooped him up and put him in the trunk of my car along with three others who also needed help, and rushed to the hospital in another city. After dropping them there, I went back to see if my family was OK.

When I returned after four hours, they were all taken to a hospital in Reyhanli, Turkey. I received a text on WhatsApp that my brother had died. I lost nine members of my family that day.

Then I heard that the hospital I was at had also been bombed. It was a blur. Everything was happening at once.

My life has changed. I can't sleep. I haven’t slept for days, not even for a minute. When I am not crying over my brother, I am worried about my mother, my kids and my family who are being treated in Turkey. This is the worst a man can endure, knowing that you can’t do anything to help your family, that you can’t protect them.

Before the revolution, I used to work as a government employee, and I continued till I got fired after the rebels liberated our area in Idlib. My brother and I set up a small shop and that’s how we could feed our families. I am a regular man. I don’t care about politics. I didn’t care about the revolution.

Malhum was my only brother. He was my best friend for 35 years and my business partner. I’m left with nothing of him but his four children who’ve been orphaned by this war.

Birds in heaven

Abir Al Saleh: 32

Four years ago, my husband promised to bring us to Turkey after finding a job and a house. The last time I heard from him he was leaving me to marry another woman there.

I have four children: 12-year-old Hadeel; Batul, 10; Ruba, seven; and the youngest child, Mohamed, who is four.

I have been working as a labourer in a local farm to feed my children. Usually I start at 5:30 in the morning and work two shifts a day, barely making enough to feed my children. Ruba suffered from thalassemia. I scraped and saved every penny to pay for her blood transfusions. It was hard.

I was working in the fields that morning. Someone told me there had been an attack. I rushed back home as soon as I heard it but I couldn’t find any of my children. I was desperate and thought I would lose my mind. I started running on the streets like a mad woman, fearing the worst, asking anyone I could find if they had seen my kids. An old man told me that they'd been taken to a hospital but he didn’t know the name.

Hours later, just before sunset, while we were running from one hospital to the other, someone told me my children were dead.

I felt my heart breaking into pieces inside me. I knew they were gone but a tiny voice in my head kept saying: "What if they are still alive?" I felt like the world was spinning around me. I wanted to throw up. I fell unconscious.

For the past six years since the war began, I have never felt safe. I always knew I could lose someone close to me at any time, at any moment. The fear is constant. It’s what we wake up to and feel in our hearts each time we go to bed. We have nowhere to go and nowhere to hide. This is our reality. I made peace with the idea of death during this war but never in my wildest imagination did I think I would lose my four children all at once. I have lost my will to live.

I keep thinking of Ruba, my poor Ruba, who was suffering so much all her life. She found peace at last. Her death brought an end to her suffering. I guess that’s my only relief ... that my children have now become birds in heaven.

A ghost town

Muhamed Al Mansour, 36

The pain I feel in my heart is more than the pain that hurts my lungs each time I breathe. I haven’t slept properly for even a day since the attack happened. Every time I close my eyes, I feel like I am choking.

Even now as I speak, I can hear two Russian jets flying overhead. They usually come in pairs ... the outskirts of Khan Sheikhoun have just been bombed right now.

I used to drive trucks before the war. Three years ago, I left Allatamna in Hama province with my entire family. The constant fighting there was unbearable. I moved to Khan Sheikhoun and started working as a volunteer for the civil defence group.

On the morning of the attack, the bomb fell right in front of my brother’s house. Omar was my only brother. I heard the bomb falling on his neighbourhood and rushed there to help.

When I got there I felt sick. My nose started bleeding. My eyes burned and my head was throbbing with pain. I looked around and saw people foaming from their mouths.

My brother had died instantly because he was very close to where the bomb fell.

Khan Sheikhoun is under constant bombardment. It’s close to the Hama frontline. There's been intense fighting for the past month in Hama. I didn’t know it was a chemical attack till I got there. The people who were trying to help the injured were collapsing on the ground.

As a White Helmets volunteer I have seen hundreds of people dying. I have helped people with their limbs blown off. I have dug mangled bodies out of debris but this was the first time when I felt completely helpless. I didn’t know what to do. There were dozens of people on the ground but I didn’t know how to save them. I took their clothes off to let them breathe.

Khan Sheikhoun, which according to activists sheltered nearly 100,000 people, now looks like a ghost town. People are terrified. The internally displaced people are scared of coming here. Life seems to be standing still. People have disappeared from street corners. The residents who lived in the neighbourhood that was attacked have moved to a different one.

I have lost my only brother but I will keep walking the same path in helping people. What else can I do?

I was released from the hospital a couple of hours ago and as soon as I’m back on my feet I’ll go back to doing my job as a volunteer for the White Helmets. I will go to every neighbourhood that’s been bombed. After my brother’s death it’s all the more reason for me to help the victims.

Nightmares

Qutaiba Al Zuhouri, 32

I keep dreaming about the small boy that I saw. He was gasping for breath. He tried slowly to stagger towards me, asking for my help. But before I could do anything, he fell on the ground. He was dead. Thick foam was slowly trickling out of his mouth. It’s one of the many nightmares that keeps waking me up.

I work in Zaitounah charity organisation, based in Hama. We help children who have been orphaned in this war and provide aid to hospitals and internally displaced people. I was in Khan Sheikhoun with other volunteers to help people who were forced to leave their homes in Hama.

There are many newly displaced people, mostly women and children, who are fleeing the frontline in Reef Hama after coming under constant regime bombardment. Khan Sheikhoun is the nearest town in rebel-held areas.

I was in that neighbourhood when the attack happened. We were getting ready to get inside our cars to receive the internally displaced people who were supposed to arrive that morning. I heard a loud bang. Suddenly I couldn’t see anything except a yellow mist. We were not prepared for what was to come. I still have trouble with my vision. I feel nauseous all the time. I can’t sleep.

I keep waking up because I can’t breathe. The nightmares are relentless. I keep dreaming about the dead children that I’ve seen and couldn’t help. Seeing a child dying in front of you and not being able to help them is perhaps the worst thing that can happen to you.

In that attack, I lost one of my colleagues, Amer Nayaf, who was a civil rights lawyer. Five years ago we started the organisation together to help the victims of the war.

I am slowly recovering now in Reyhanli, Turkey. As soon as I’m back on my feet, I am going back to Syria. After this attack, I believe in our purpose even more. As long as Assad is the president, we will keep fighting our cause, even if the whole word stands against us. We will keep moving forward.

The following names were provided by the White Helmets:

Molham Jehad Al-Yousef

Yaser Ahmad Al-Yousef

Ammar Yaser Al-Yousef

Mohamed Yaser Al-Yousef

Sanaa Haj Ali

Abdel-Kareem Ahmad Al-Yousef

Ahmad Abdel-Hameed Al-Yousef

Ayah Abdel-Hameed Al-Yousef

Dalal Ahmad Al-Sah

Ibrahim Mohamed Hasan Al-Yousef

Mohamed Hasan Al-Yousef

Hend Tourki Al-Yousef

Khaled Halawa

Mohamad Awad

Nouhad Ahmad Al-Yousef

Malak Turki Al-Yousef

Nour Nouhad Al-Yousef

Hasan Mohamad Al-Yousef

Ahmad Ibrahim Al-Yousef

Emad Eddine Mohamad Al-Kadah and his three children

Tourki Al-Kadah and his two children

Nour Al-Azrak

Hind Tourki Al-Kadah

Rajaa Mohamad Al-Mohamad

Anas Al-Khaled

Anas Al-Khaled

Fatima Al-Sousi

Alaa Anas Al-Khaled

Shahd Anas Al-Khaled

Abdel-Rahman Anas Al-Khaled

Khadija Anas Al-Khaled

Shourouk Halawa

Ahmad Khaled Halawa

Shaimaa Ibrahim Al-Jowhar

Ahmad Shohoud Al-Reem Abu Mhanna

Najeeb Al-Johar

Safiyya Al-Haj Yousef

Mayar Al-Marhee

Mohamad Mohee Al-Deen Najm Al-Sayed

Seham Mohee Al-Deen Al-Sayed

Olaa Mohannad Makhzoum

Rahaf Sohail Al-Yousef

Ahmad Ezzo Najm Al-Sayed

Abdel-Ghafour Meratee

Abdallah Ghassan Al-Shehna

Riyadh Khaled Al-Kerawan

Maram Hasan Halawa

Faisal Abdel-Razek Al-Raslan

Badran Abdel-Rahman Al-Rahmoun

Ahmad Hosrum

Amer Al-Nayef

Alaa Al-Nayef

Mohamad Al-Nayef

Alaa Mohamad Al-Nayef, his wife and sister in law

Derar Al-Elewi Abu Emad

Ahmad Omar Al-Ramadan

Jamela Hafez Al-Qasem

Mohamad Jamal Al-Qasem Al-Hmoud

Fares Mohamad Saeed Al-Barhoum

Maher Mohamad Saeed Al-Barhoum

Soha Al-Qasem

Fatima Jamal Qasem Al-Hmoud

Hayan Abdallah Al-Debes

Sarah Al-Solaiman

Ahmad Hayyan Al-Debes

Mohamad Hayyan Al-Debes

Yamen Al-Shayeb

Sham Al-Shayeb

Joud Al-Shayeb

Mohamad Al-Shayeb

Sarah Mansour

Mostafa Al-Azkour

Samer

Mosa Al-Husein

Asmaa Al-Husein

Ruba Ahmad Al-Saleh

Hadeel Ahmad Al-Saleh

Batul Ahmad Al-Saleh

Mohamad Ahmad Al-Saleh

Khitam Abdel-Hameed Halawa

Hassan Youssef

Asma Hayek