Pakistan on Tuesday executed a convicted killer whose supporters say was a juvenile at the time of his crime, despite strenuous objections from rights groups and the United Nations.

Shafqat Hussain was hanged shortly before dawn at a jail in Karachi for killing a seven-year-old boy the city in 2004, his brother and a prison official told AFP.

His case drew international attention as his lawyers and family claim he was only 15 at the time of the killing and was tortured into confessing.

United Nations rights experts have said his trial “fell short of international standards” and urged Pakistan to investigate claims he confessed under torture, as well as his age.

The government of Kashmir, Hussain’s home region, urged President Mamnoon Hussain late on Monday to postpone the execution to allow further inquiries, but the hanging went ahead as planned.

“Shafqat Hussain was hanged 10 to 12 minutes before dawn prayers today,” a prison official told AFP, speaking on condition of anonymity.

Hussain’s brother Gul Zaman confirmed the news to AFP.

Hussain was originally due to face the noose in January but won four stays of execution as his lawyers fought to prove he was under 18 at the time of his offence and could therefore not be executed under Pakistani law.

A government-ordered probe to determine Hussain’s age, carried out by the Federal Investigation Agency, ruled he was an adult at the time of his conviction—though the results have not been published officially.

Pakistan has hanged around 180 convicts since restarting executions in December after Taliban militants massacred more than 150 people at a school, most of them children.