Women and children who had taken refuge from the shelling that has continued unabated for the last 20 days, were killed.
That day, our teams were in the same area delivering parcels and supplies to families hiding from the current violence. That day we were lucky, we were not at that school.
Every day, the number of people killed and injured in Gaza rises. And every day, we head out to deliver parcels filled with canned meat and beans, rice, powdered milk and cooking oil, as well as other items needed such as blankets, wet wipes, disposable diapers, soap and toothpaste, to the survivors who have had to flee. When people leave their homes, they usually grab what they can carry - often it is a blanket or some spare clothes, sometimes they also manage a favourite book or a framed picture of a loved one.
When they arrive at the shelters, warehouses or abandoned apartment buildings - wherever they have chosen to seek a safer place to hide - they are in need of everything you might imagine to survive and retain a sense of normalcy and dignity. And each time they have to run, it starts all over again. In just three weeks, there are now more than 150,000 people in Gaza who have no or damaged homes, or can't go back to their homes because of ongoing fighting.
We often find people in makeshift shelters running out of food and too terrified to move. There is no or very limited access to water and electricity and there is no fuel to run generators. And there is a critical shortage of medical supplies and surgery rooms in hospitals due to the increasing number of injuries following the ground incursion. Already, 17% of the population is disabled - and this number is rising fast.
Yesterday, during the 12-hour truce, I was out with assessment teams trying to reach as many families as possible. I met a woman by the name of Saeda. Three days ago, at 3am, Saeda was forced to flee from Beit Hanoun with her family. Her family were having a light meal before the fasting of the day started (it is Ramadan) when they heard extreme and continuous near shelling. They all fled onto the street, terrified of being shot. They were overtaken by white gas bombs and became disorientated but they kept running. Saeda lost control of her family. Now, her eight-year-old daughter, Ola, is missing. Saeda is sheltering in a school and just wants to know whether Ola is alive or dead.
We hear time and time again that it is the young and vulnerable who suffer most in times of war and this has never been more true than now. In Gaza, the average age is 17. Children are dying. And if they are not being killed, they are suffering significant trauma. The latest reports suggest that over 100,000 children will need specialised psychosocial support following this escalation of violence.
Mercy Corps has been working in Gaza for over two decades - we run psychosocial programmes for children, provide basic needs support and we are developing entrepreneurship and women's involvement in the tech sector. But right now our normal programmes are on hold as we focus on getting people the food and emergency items they need to stay alive. With 87 staff members and a network of over 50 community based organisations, we have the largest humanitarian programme in Gaza after the UN.
Our staff too have been personally affected. Some have been injured, some have lost their homes and some have lost members of their families. Last week, one of my colleagues lost eight members of his family in one day. Gazans are suffering. We feel unsafe, and the situation is escalating day by day. We don't know when it is going to end.
But next week, my team will be on the move again, we are aiming to distribute food and non-food parcels to another 10,000 people (more than 2000 families) and we will also begin distributing 8000 hygiene kits in partnership with others to hospitals and clinics in Gaza, as well as 5000 heavy plastic tarps for temporary windows and doors and some parts of roofs of damaged homes.
I was asked by someone yesterday if it was still safe for our teams to be in Gaza. I am Palestinian. Most of my colleagues are Palestinians. These are our homes, our families. Yes, we operate in a very risky and dangerous environment, but if we don't help them, who will?
Mercy Corps has joined with other international aid organisations calling for a lasting ceasefire in Gaza. But right now, until there is a change in the situation on the ground, all we can do is help people survive - and wait.
Mercy Corps is the only global humanitarian organisation with its European headquarters in Edinburgh. Operations in the field are supported by the HQ and public donations are vital. Go online to www.mercycorps.org.uk to donate.