As a father was registering his twins' birth in Gaza, an airstrike killed the 3-day-olds and their mother at home

LONDON and GAZA STRIP -- When he left his home on Tuesday morning to get birth certificates for his newborn twins, Mohammed Abu al-Qumsan never imagined he would return with their death certificates instead.

In a matter of minutes, an Israeli strike on the Qastal Tower building, in Deir Al-Balah, where the Abu al-Qumsan family was living after having been displaced from the north of Gaza, killed his 3-day-old twins, Aser and Aysel, together with their mother, Dr. Jumann Arfa, and grandmother, according to family members.

The twins were born on Saturday, Aug. 10, as written on their birth certificate. On that day, Dr. Arfa shared the news in a Facebook post, with friends welcoming her babies in war-torn Gaza and praying for their health and safety.

Now the few comments to congratulate the birth below the announcement are overshadowed by hundreds of condolences to the family.

"I helped her raise funds for her to deliver the twins safely. I only spoke with her yesterday, my heart is truly broken," a friend wrote.

The Israel Defense Forces in a statement to ABC News said, "The details of the incident as published are not currently known to the IDF."

The military added, "The IDF is fighting against the murderous terrorist organization Hamas in Gaza following the massacre on October 7. Unlike the terrorist organization Hamas, the IDF targets only military objectives and employs various measures to minimize harm to civilians."

Abu Al-Qumsan learned about the news from his brother-in-law, Fera Arafa, who told ABC News that he survived the explosion because he was out to buy bread.

"I went to register the children the day before. They said to come back tomorrow. So I went and I was waiting when someone called me, telling me that the apartment which I live in was bombed," Abu Al-Qumsan told ABC News.

As soon as he got the call, Abu Al-Qumsan said he rushed to the nearby Al-Aqsa Hospital, where he was told the babies and mother had been taken.

Shock and pain overtook him when he saw with his own eyes that the news was true, he said. Videos show him collapsing and shaking, unable to contain his desperation. The couple married in July last year and lived in Gaza City, where she worked as a pharmacist and he worked as a sales representative until Oct. 13, 2023, when they were forced to evacuate to southern Gaza.

At Al-Aqsa Hospital, Arafa grieved as he held his brother-in-law and worried about the future of his remaining family.

Arafa told ABC News he was living in the same apartment as his mother, sister, her husband and their babies. The apartment that was "filled with joy and happiness since the twins came to this life," he said.

Now a massive hole in the building is a reminder of the deadly attack that put an end to that happiness. It also punctuated the difficulties endured by Abu Al-Qumsan and his family in the last 10 months of war in Gaza: the displacement, the lack of resources, and the pregnancy, carried on during what international humanitarian organizations and the United Nations called a collapsed health system.

"Minutes before the explosion, I was outside the house, my mother phoned me and told me that she wanted bread," Arafa told ABC News about the morning the Qastal tower apartment was hit. "Minutes after I ended my call with her, a friend called me and told me they had all been killed."

Arafa said he was overcome by shock.

"What is the reason? I still can't believe it. A few minutes ago, I was talking to my mother on the phone," he said. "We are civilians, and we are looking for our livelihood to provide for our daily needs, we have no connection to organizations, parties, or the military, I do not know why we were bombed."

What began as a simple task of securing birth certificates transformed into a heart-wrenching journey to bury his family and obtain their death certificates, but Mohammed's sorrow is not unique, according to a spokesperson for the Hamas-run Ministry of Health, who told ABC News this is part of a larger tragedy affecting countless families.

"This attack wiped out the entire family from the civil registry, raising the number of newborn deaths to 115 children since the beginning of this conflict," Dr. Khalil Al-Daqran, spokesperson for Al-Aqsa Martyrs Hospital and the Ministry of Health, told ABC News.

Al-Daqran said they are struggling to deal with the psychological pain too.

"The psychological and emotional impact on the father of the two children who were killed is profound. We have approximately 10,000 patients suffering from psychological disorders, most of whom are left untreated and are seen wandering the streets."

As for the measures and protection for infants and newborns, Al-Daqran said the attacks are directed at every citizen in the Gaza Strip, making it impossible to protect children, and that the lack of aid and resources is affecting the youngest disproportionally.

Thousands of "children have been killed in this brutal conflict over the course of just 10 months. When the authorities closed the [border] crossings and deprived these infants and newborns of baby formula, the situation became even more dire. Tragically, a significant number of newborns have lost their lives due to malnutrition too," he said.

Two days after the Abu al-Qumsan family lived their tragedy, the number of Palestinians killed in the Gaza Strip since Oct. 7, when Hamas militants carried on a surprise attack that left over 1,200 killed and hundreds kidnapped, reached the grim milestone of 40,000, on top of the over 90,000 injured, the health ministry said.

According to the ministry, about 11,000 children are among the dead.

"These appalling atrocities have become tragically commonplace, as relentless, indiscriminate assaults continue to claim the lives of so, so many children and leave countless families devastated. Surely, surely, it must be stopped," a spokesperson for the United Nation Children's Fund (UNICEF), said in a statement to ABC News.