(CNN) Three men were executed by firing squad in Bahrain on Saturday morning, according to the kingdom's state news agency.

The move came days after the United States announced it would be reinstating the federal death penalty for the first time in nearly two decades.

The executions were confirmed by Bahrain's advocate general and chief of anti-crime prosecution, Ahmed al Hammadi, Bahrain News Agency (BNA) said.

The men were convicted in two separate cases by the High Criminal Court after each investigation from Bahrain's Public prosecutor called for them to receive the maximum sentence, BNA said.

Bahrain's public prosecutor said that two of the executed men were convicted of "joining a terrorist group, committing murders, and possessing explosives and firearms to carry out terror acts."

There were 58 other individuals accused in the case, 19 of whom were sentenced to life in prison, according to BNA. Two were acquitted, it said.

Two of the men, Ali al-Arab and Ahmed al-Malali were sentenced to death by the court and the rulings were upheld by the Court of Appeals and the Court of Cessation.

In February 2017, the pair were arrested and sentenced "in a mass trial marred by allegations of torture and serious due process violations," according to a Human Rights Watch report.

For months, human rights groups have called for an examination of the circumstances around the men's sentencing and for the Bahrain government to halt al-Arab and al-Malali's executions.

In May, a group of United Nations human rights experts said there were "serious concerns" that the pair were "coerced into making confessions through torture and did not receive a fair trial."

During the arrest, al-Malali was reportedly shot in his hand. Two bullets were allegedly only removed from his hand 23 days later, according to the UN statement.

Before the conviction, al-Arab was "reportedly forcibly disappeared for a month," the UN statement said.

Al-Malali was charged with "possession of firearms, membership in a terrorist cell and the alleged killing of a security officer," according to the UN statement.

Al-Arab was charged with "killing a police officer, firing on a security patrol and injuring one of its officers, assisting in an attempted prison escape, and possession of firearms," the UN statement said.

The men were "allegedly prevented from attending their trial, sentenced to the death penalty in absentia and stripped of their nationality, which was later reinstated," according to the UN statement.

They were both were reportedly tortured and forced to sign confessions of their crimes it said.

"The two individuals should have never been convicted on the basis of what appears to be seriously flawed trials. Executions in these conditions would amount to arbitrary executions," the UN experts said.

On Friday, Agnes Callamard, the UN's special rapporteur on extrajudicial, summary or arbitrary executions issued a last-minute push to halt their executions.

"I remind Bahrain that the only thing that distinguishes capital punishment from an arbitrary execution is full respect for the most stringent due process and fair trial guarantees," Callamard said in a statement.

The third man executed on Saturday had been convicted of killing and dismembering an imam and subsequently sentenced to death in a unanimous decision by the court, according to BNA.

A 'green light'

Prominent Bahraini human rights defender Maryam al-Khawaja told CNN on Saturday that Bahrain's "justice system -- if you can call it that -- is a main tool of silencing dissent."

Rights groups and human rights defenders like al-Kahwaja have long criticized Bahrain for its crackdown on anti-government protests and dissent.

Al-Khawaja added that it's no coincidence that Bahrain's move to execute the men came shortly after the US announced it would bring back the federal death penalty

A statement from the Embassy of the Kingdom of Bahrain in Washington on Friday read: "Just as capital punishment is permitted in the United States, the Kingdom of Bahrain allows judges to impose death sentences in cases of serious crimes..."

Al-Khawaja said, "We have seen this before."

"A lot of times you will see that Bahrain likes to feel they are safe when they are about to commit violations. So they look to their allies to make sure they aren't going to be held accountable," she said.

"When one country commits a human rights violation, and if they don't face international consequences, then you see another country doing the same," she added, saying that Bahrain saw the US' announcement as a "green light."