LONDON — Public executions returned to the streets of Iran last week as the regime clamps down on public dissent following months of war with the U.S. and mass protests in January, according to recent statements from human rights groups and family members of those executed.

Cranes were used to set up hanging ropes in Isfahan, a central city in the country, to execute three young protesters.

Amirhossein Safari, 27, Abolfazl Sepahi, 23, and Alirez Sepahi, 25, were brought by van to Isfahan’s Alikhani Street to be hanged for alleged crimes related to protests against the regime in January, according to human rights groups.

The Islamic Republic regime in Iran has executed at least 56 people on national security-related charges since March 19, including 27 individuals in cases linked to nationwide protests in January, United Nations High Commissioner for Human Rights Volker Türk said in a statement Wednesday. More than 100 others are at risk of execution on similar charges, Türk warned.

Iranian lawyers inside the country told ABC News that the real number of people at risk of execution on charges related to the protests against the regime could be higher.

In the Alikhani case, 12 young men were sentenced to death and several others were sentenced to five to 10 years in prison, according to Iranian judiciary and human rights sources. Of the 12 men sentenced to death, four have been hanged and eight others currently await execution.

Protest at the scene of Isfahan’s public execution

In the early hours of Tuesday, July 28, when news circulated about the regime’s planned execution of the three young men, scaffolding was installed at Isfahan’s Alikhani Square, with a crane brought to the scene as security forces gathered.

It raised fears that the executions could be carried out in public. Soon, a group of citizens gathered at the site.

Eyewitnesses told ABC News that the van transporting the defendants arrived at the location, escorted by a truck with a machine gun on its back to scare off protesters at the execution scene.

Videos shared online showed protesters chanting slogans, clashes breaking out and people fleeing as security forces moved in.

The defendants arrived at dawn, just before the morning prayer call, the time when the regime’s laws mandate execution sentences be carried out.

Many Iranians reacted to the execution on social media by sharing posts about how the morning prayer call scares them, as it has now turned into a reminder of a “death song” to them.

While Safari and Abolfazl Sepahi were hanged Thursday, Alireza Sepahi did not reach the gallows and was taken to a hospital after he collapsed from what human rights groups described as heatstroke or a heart attack.

Torture and forced confession on prisoners and pressure on families

Several relatives and friends of the defendants in the Alikhani case told ABC News that the regime has forced their children to confess. They said the defendants have been subjected to different forms of severe physical and psychological torture for days and were not allowed to have a lawyer of their choosing.

The families asked not to be named for their own security and to prevent additional pressure on their young men on death row. In some cases, the court refused to accept evidence that the defendants had not been at the scene of the alleged crime at the time, the families added.

“They have tortured them for days to confess to murder,” a family member said.

Even the pro bono lawyer for the defendant, who was assigned by the judiciary, did not have access to the case during the trial and was still refused access after the death sentence was issued, according to the family member. They also said the lawyer and defendant’s parents were informed about the death sentence only after it was issued by the court.

The U.N.’s Türk condemned the death sentences in this case in his statement last week and expressed concern over the judicial process and reports of what the statement described as confessions that have “allegedly been obtained under torture and other ill-treatment.”

“The death penalty is incompatible with the right to life and irreconcilable with human dignity,” Türk said. “Such punishment has no place in our world.”

Amnesty International condemned the recent hangings in Iran in a statement Tuesday following the hanging of Safari and Sepahi, warning that among those prisoners on death row are three whom the organization said were arrested as children.

“The muted response from the international community emboldens the Iranian authorities to continue their deadly rampage. UN member states must take urgent coordinated diplomatic action to press the Iranian authorities to halt further executions,” the Amnesty International statement said, in part.

Family members and friends of those on death row have repeatedly been warned by security and intelligence forces not to talk to the media and have been warned not to contact families of other defendants in the same case or else they would face consequences.

“The whole family’s life is on fire. It is not just the life of one single person at risk. We are all at risk,” a family member’s relative told ABC News.

Several sources close to imprisoned protesters told ABC News that the regime has threatened them, saying that that if they talk to the media, their other children also would not be safe.