"Why did they (soldiers) shoot her to death, for what crime? And what sin have we committed?" the girl's sister said from an undisclosed location. "What have we done? And what has the child done?"

CNN is not naming the father, sister or doctor for security reasons.

While in the house, the sister said security forces took away her brother. They have no information as to his whereabouts or even if he is alive.

"He was arrested by the military and (we're) not sure whether he is alive or not. We have no information from him yet," she said.

"We dare not go home till now and are still in hiding," she said. "There are still soldiers and police in our house."

More than 20 children killed

Anti-coup protests and strikes have since gripped the nation but are being violently suppressed by the junta's police forces and military soldiers, with widespread reports of shootings, enforced disappearances and torture of political prisoners.

At least 320 people have been killed in the bloody crackdown, according to advocacy group Assistance Association for Political Prisoners (AAPP), though activists say the death toll is likely much higher. More than 20 of those deaths are children, humanitarian organization Save the Children said.

Many residents in towns and cities across the country live in fear of being dragged out of their homes in nighttime raids by security forces. Almost 3,000 people have been detained since February 1, according to AAPP. Many of them are young people and students and their families often have no idea where they are being held or what condition they are in.

Worried the military would attempt to seize Khin Myo Chit's body, her sister said they had difficulty burying her according to the Muslim tradition.

"We have to bury her without letting everyone know (and) we couldn't go with funeral cars as we worried they might steal her body, we could only use the house cars for her funeral," she said.

"When we got to the cemetery, a few people were there so we had to hide her body, we had to wait until they were gone and only when no one was around could we bury her."

The family have been unable to mourn the young child properly. Instead, they have been forced to leave their home and keep watching over their shoulders, terrified they may be picked up by junta forces.

"It's not surprising at all that soldiers are also willing to seize protesters' bodies to short circuit efforts to mourn them, and recognize them as martyrs," said Phil Robertson, deputy Asia director at Human Rights Watch.

"That's why this grieving family is forced to hide, and surreptitiously bury their child, because the military fears what they represent, which is an aggrieved family who have every reason in the world to cry to the heavens about the loss they have suffered," added Robertson. "The Tatmadaw wants their voices silenced, and will not hesitate to use force to make it so."

'A slaughter ground'

Khin Myo Chit's death has come as a shock even amid the relentless stream of deaths and arrests in Myanmar.

The doctor who received her body said he had lost count of the number of dead and injured that have passed through his clinic. The streets of Mandalay have become "like a slaughter ground" with security forces shooting at "anything they see," he said.

"What they are doing is not cracking down the protest, now they are shooting randomly in the neighborhoods, it's not safe anymore even in our own houses with locked doors," the doctor said. They are asking houses to open for them, and do as they like."

The doctor said hospital workers were hiding bodies to keep them safe from soldiers so they could be handed back to the families.

Myanmar's military has not yet officially commented on Khin Myo Chit's death, but has repeatedly defended security forces' response to the protesters, saying they use minimal force. UN officials, however, have said the military's actions against civilians "likely meet the threshold for crimes against humanity."

United Nations Special Rapporteur on human rights in Myanmar, Tom Andrews, said Thursday the international response to the military coup in Myanmar is "falling short" of what's needed to avoid further turmoil, and urged UN member states to hold an emergency summit.

"The limited sanctions imposed by member states do not cut the junta's access to revenue that help sustain its illegal activities, and the slow pace of diplomacy is out of step with the scale of the crisis," Andrews said.

It came after the United States and United Kingdom announced sanctions against military-owned conglomerates as part of further measures targeting the Myanmar military regime. The US designated Myanmar Economic Holdings Public Company Limited (MEHL) and Myanmar Economic Corporation Limited (MEC), which control large sectors of the country's economy, including alcohol, cigarettes, consumer goods and mining and banking.

The UK sanctioned the MEHL over evidence it said the company contributed funds to support the military in its campaign of ethnic cleansing against the Rohingya in 2017.