09/04/2015 19:14 BST | Updated 09/06/2015 06:59 BST

Yemen: A Humanitarian Catastrophe

It was 2:30 in the morning on Thursday 26 March, in Sanaa, Yemen. I thought, and in fact I hoped, I was being shaken awake by a severe thunderstorm. Things had been heating up across Yemen for months, but no one had forecast this type of storm.

The deep booms quickly gave way to anti-aircraft gunfire, jolting me out of bed. With no electricity I quickly felt around for whatever clothes I could grasp in the darkness. I yelled for my colleagues and ran downstairs as fast as I could while keeping myself crouched low, below the windows.

Down in a safer space my colleagues and I waited out the first night of Operation Decisive Storm. I forced myself to take refuge in logic, 'we are in a civilian house, there's no way anyone would target us.' I convinced myself we were safe as the sounds of war filled the air. When daylight came, fighting gave way to the sound of singing birds. Full of adrenaline, not one of us would get back to sleep. We would not sleep for the next five nights.

Working around the clock our security advisor kept us up to date on what was going on, and where. We learned that the airport had been hit, and that sea and air routes into the country had been closed. My first thought: we are going to plunge into humanitarian disaster.

Yemen relies on imports to meet more than 80% of national food consumption. Basic staples are very important, and wheat is 90% imported and rice is 100% imported. Before the current conflict already more than 10million Yemenis did not have enough food to eat. Out in the field I regularly meet families who drink tea and eat only biscuits for dinner, children who go to bed hungry every night. With imports a food supply lifeline for Yemen, the closure of sea and air routes threaten to claim perhaps the highest death toll in this latest round of conflict.

Already some 16million Yemenis - more than 60% of the population - needed humanitarian assistance before airstrikes began. The numbers are now climbing, yet no regular imports of food, fuel or medical supplies have reached the country for the past two weeks.

The third night of airstrikes was the worst. One I will never forget. I struggled to text my family as I shook like a leaf from head to toe. Waiting out the storm in an internal room, three walls between us and the fighting, I tried to breathe deeply as the entire house shook with each impact. It sounded like the doors were being bashed, about to fall in. My falsely constructed sense of safety was now impossible maintain. My colleagues and I were terrified and tired.

Evacuation the following day was tense. It was our third attempt. The aircrew held hands and cried as we took off, scared like the rest of us that the plane would be shot down. We left luggage on the runway. We left loved ones behind. But no one said a word. We had to go. We had no choice. There was no warning for any of this.

We are safe now, but our hearts and minds are still in Yemen, trying to help those trapped in the terror. They need food, fuel and medical supplies. Hundreds have been killed, and tens of millions are in danger. The conflict needs to stop and sea and air routes should be opened right now in order to facilitate the delivery of essential supplies to those in need.

Oxfam has delivered cash vouchers, water containers and water filters to some of the people caught up in the violence. It is also sending water trucks to some of the most vulnerable areas in Hodeidah. It plans to reach one million people. Oxfam has worked in Yemen for 30 years.