The family of a 67-year-old midwife from a remote village in North Waziristan told lawmakers on Tuesday about her death and the "CIA drone" they say was responsible. Their harrowing accounts marked the first time Congress had ever heard from civilian victims of an alleged US drone strike.

Rafiq ur Rehman, a Pakistani primary school teacher who appeared on Capitol Hill with his children, Zubair, 13, and Nabila, 9, described his mother, Momina Bibi, as the "string that held our family together". His two children, who were gathering okra with their grandmother the day she was killed, on 24 October 2012, were injured in the attack.

"Nobody has ever told me why my mother was targeted that day," Rehman said, through a translator. "Some media outlets reported that the attack was on a car, but there is no road alongside my mother’s house. Others reported that the attack was on a house. But the missiles hit a nearby field, not a house. All of them reported that three, four, five militants were killed."

Instead, he said, only one person was killed that day: "Not a militant but my mother."

"In urdu we have a saying: aik lari main pro kay rakhna. Literally translated, it means the string that holds the pearls together. That is what my mother was. She was the string that held our family together. Since her death, the string has been broken and life has not been the same. We feel alone and we feel lost."

An Amnesty International report, published last week, lists Bibi among 900 civilians they say have been killed by drone strikes, a far higher number than previously reported. The Amnesty report said the US may have committed war crimes and should stand trial for its actions.

The US has repeatedly claimed very few civilians have been killed by drones. It argues its campaign is conducted "consistent with all applicable domestic and international law". Unofficial reports, however, have suggested that hundreds have been killed in Pakistan alone, with up to 200 children killed.

In poignant testimony, Rehman's son, Zubair, described the day of the attack, the day before the Muslim holy day of Eid, as a "magical time filled with joy". He told lawmakers that the drone had appeared out of a bright blue sky, the colour of sky most beloved by his grandmother and himself, he said.

"As I helped my grandmother in the field, I could see and hear the drone hovering overhead, but I didn’t worry" he said. "Why would I worry? Neither my grandmother nor I were militants."

"When the drone fired the first time, the whole ground shook and black smoke rose up. The air smelled poisonous. We ran, but several minutes later the drone fired again. "

"People from the village came to our aid and took us to hospital. We spent the night in great agony in at the hospital and the next morning I was operated on. That is how we spent Eid."

Zubair said that fear over the drone attacks on his community have stopped children playing outside, and stopped them attending the few schools that exist. An expensive operation, needed to take the shrapnel out of his leg, was delayed and he was sent back to the village until his father could raise the money, he said.

“Now I prefer cloudy days when the drones don’t fly. When the sky brightens and becomes blue, the drones return and so does the fear. Children don’t play so often now, and have stopped going to school. Education isn’t possible as long as the drones circle overhead.”

According to Zubair, the fundraising took months.

His sister, Nabila, told lawmakers that she had been gathering okra with her brother and grandmother when she saw a drone and "I heard the dum dum noise."

"Everything was dark and I couldn't see anything. I heard a scream. I think it was my grandmother but I couldn't see her.

"All I could think of was running."

Rehman told lawmakers that he is seeking answers to why his mother was targeted. The strike has affected his wider family, who no longer visit because they fear the drones might kill them too.

In testimony that caused the translator to stop and begin to weep, he said: "Congressman Grayson, as a teacher, my job is to educate. But how do I teach something like this? How do I explain what I myself do not understand? How can I in good faith reassure the children that the drone will not come back and kill them, too, if I do not understand why it killed my mother and injured my children?"

He said that his mother was not the first innocent victim of drone strike, but that "dozens of people in my own tribe that I know are merely ordinary tribesman had been killed". He said that numerous families in his community and the surrounding area had lost loved ones, including women and children over the years.

"They have suffered just like I have. I wish they had such an opportunity as well to come tell you their story. Until they can, I speak on their behalf as well. Drones are not the answer."

Rehman said that although the Pakistani government accepted his claim and confirmed details, it said it was not responsible and he has had no compensation to help with the medical treatment for his children.

Rehman said: "In the end I would just like to ask the American public to treat us as equals. Make sure that your government gives us the same status of a human with basic rights as they do to their own citizens. We do not kill our cattle the way US is killing humans in Waziristan with drones. This indiscriminate killing has to end and justice must be delivered to those who have suffered at the hands of unjust."

Asked what he would say to President Barack Obama, Rehman called on the Pakistani and US government to work together to achieve peace.

"I would say to President Obama if I had the opportunity to meet with him is: 'What happened to me and my family was wrong'. I would ask him to find an end, a peaceful end, to what is happening."

"I think that's something that the American government and the Pakistani government can work together to achieve."

Missing from the briefing on Tuesday was the account of Shahzad Akbar, an international critic of US drone policy and the family lawyer, who spearheaded the idea of bringing civilian victims of drone strikes to Congress and who was refused a visa for the third time. Reprieve, the British rights group which together with Brave New Foundation, helped the Rehman family travel to Washington, said he had 6,000 letters supporting his visit.

The hearing was attended by only five members of Congress, and Grayson said such low numbers of lawmakers at hearings were not unusual. Those attending were all Democrats: Rush Holt of New Jersey, Jan Schakowsky of Illinois, John Conyers of Michigan, Rick Nolan of Minnesota, and Grayson, the Florida Democrat responsible for inviting the family to Washington and for holding the hearing.

Each of the lawmakers spoke about the drone programme to call for more transparency or greater oversight. Schakowsky said she agreed with Amnesty International and Human Rights Watch and their call for more transparency and debate about the targeted killing programme. Holt and Conyers called for a congressional investigation into drone strikes.

Grayson, a fierce critic of the wars in Iraq and Afghanistan told the hearing: "Invading from the skies is no different from invading on the grounds. We should never accept that children and loved ones are acceptable collateral damage.” Was there any other human activity, he asked “where 10-30% of the dead are innocent?”

It began with a broadcast of Unmanned: America's Drone Wars, a film by Robert Greenwald of Brave New Foundation, which features the Rahman family.