At least 1,634 people were executed in 2015, according to Amnesty International annual figures, which were released Tuesday evening. This marked a rise of some 50 percent from the year before and the highest number recorded by the organization since 1989.

According to the rights group, three countries — Iran, Pakistan and Saudi Arabia — were responsible for almost 90 percent of total recorded executions this year. These figures, importantly, do not include executions in China. Amnesty International stopped attempting to record data on executions in China in 2009 because of restrictions on access to information. Researchers believe the annual figure in China likely numbers in the thousands, making Beijing the world's leading practitioner of capital punishment.

Not for the past 25 years have so many people been put to death by states around the world, said Salil Shetty, Amnesty International's secretary general, in a statement. "Iran, Pakistan and Saudi Arabia have all put people to death at unprecedented levels, often after grossly unfair trials. This slaughter must end."

Shetty notes that only a minority of the world's nations still have capital punishment on the books; the United States is conspicuous as the only country in the Americas to have carried out an execution in 2015.

Here are some details on the three countries (the U.S. followed Iran, Pakistan and Saudi Arabia, with 28 executions in 2015), plucked from the Amnesty news release:

Pakistan continued the state-sanctioned killing spree it embarked on when it lifted a moratorium on civilian executions in December 2014. More than 320 people were sent to the gallows in 2015, the highest number Amnesty International has ever recorded for Pakistan.
Iran put at least 977 people to death in 2015, compared to at least 743 the year before – the vast majority for drug-related crimes. Iran is also one of the world’s last executioners of juvenile offenders, in flagrant breach of international law. The country put to death at least four people who were under 18 at the time of the crime for which they were convicted in 2015.
In Saudi Arabia, executions rose by 76% on 2014’s figures, as at least 158 people were put to death last year. Most were beheaded, but authorities also used firing squads and sometimes displayed executed bodies in public.

Iran and Saudi Arabia are regional adversaries – the former a Shiite theocratic state, the latter a kingdom that sees itself the custodian of Sunni Islam. An execution in Saudi Arabia of a prominent Shiite cleric in January prompted a dangerous political crisis with Iran, where protesters stormed the Saudi embassy in Tehran.

Pakistan, meanwhile, reacted to a ghastly 2014 terror attack in Peshawar by scrapping an unofficial moratorium on executions. The death sentences carried out, though, did not include that many charged on terror-related offences, according to Champa Patel of Amnesty International's South Asia office.

"At a time when a majority of countries have abolished the death penalty, it is alarming that Pakistan has decided to move so fast in the opposite direction," Patel said in a statement. "The death penalty is always a rights violation, but its use in Pakistan is all the more troubling given the serious fair trial concerns – including insufficient access to lawyers and endemic police torture to extract 'confessions.' "

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