Amnesty International has condemned the decision by authorities in the state of Georgia to execute death row prisoner Troy Davis.Troy Davis, 42, who had been on death row since 1991, was executed by lethal injection at the Georgia state prison in Jackson on Wednesday, despite serious doubts surrounding his conviction.On the same day, Iran publicly hanged a 17-year old boy convicted of killing a popular athlete despite international prohibitions against executing juveniles, while China executed a Pakistani national convicted of drug smuggling even though drug offences do not meet the threshold for “most serious” crimes in international law.“This is a bleak day for human rights worldwide. By executing these individuals, these countries are moving away from the global trend to abolish the death penalty,” said Guadalupe Marengo, Amnesty International’s Deputy Director for the Americas.“Countries that retain the death penalty very often defend their position by claiming that their use of the death penalty is consistent with international human rights law. Their actions yesterday blatantly contradict these claims,” she said.Amnesty International activists have campaigned extensively against the death penalty. In recent days, nearly one million signatures on Troy Davis’ behalf have been delivered to authorities in Georgia to urge them to commute his death sentence: vigils and events have been held in approximately 300 locations around the world.Troy Davis was sentenced to death in 1991 for the murder of police officer Mark Allen Macphail in Savannah, Georgia. The case against him primarily rested on witness testimony.Since his 1991 trial, seven of key nine witnesses recanted or changed their testimony, some alleging police coercion.Iranian teenager Alireza Molla-Soltani was hanged Wednesday morning in front of a large crowd in the city of Karaj.He was sentenced to death last month for stabbing Ruhollah Dadashi, a popular athlete during a driving dispute on 17 July. The 17-year old said he panicked and stabbed Ruhollah Dadashi in self-defence after the athlete attacked him in the dark, according to local media reports.Zahid Husain Shah, who was arrested in 2008 for drug smuggling, was executed in China by lethal injection on Wednesday.On the same day, Lawrence Brewer was also executed in Huntsville, Texas. He was sentenced to death for his role in the killing of James Byrd, Jr. in June 1998.Amnesty International opposes the death penalty in all cases, without exception.“The death penalty is a symptom of a culture of violence, not a solution to it,” said Guadalupe Marengo.“Hopefully the harrowing executions that have been carried out today will spur Amnesty International members, and other activists on to continue the fight against the death penalty,” she added.In addition to the USA, China and Iran, the Amnesty International’s campaign to abolish the death penalty is focusing on Belarus.Amnesty International is working with the NGO Human Rights Centre Viasna, in Belarus, calling on President Lukashenka to immediately suspend executions and commute the sentences of all those on death row.As many as 400 people may have been executed in Belarus since the country gained independence in 1991.After a year without executions, the Belarusian authorities executed two men in 2010 and sentenced three people to death and two other men were believed to have been executed between 14 and 19 July 2011,although there has been no official confirmation of the deaths.Belarus is the last country in Europe and the former Soviet Union that still carries out executions.“It is time the USA, China, Iran and Belarus recognise how isolated they are in the world,” said Guadalupe Marengo.