Indonesia on Thursday rejected mounting international pressure and desperate pleas from relatives to halt the execution of 14 drug convicts who are expected to imminently face the firing squad. The group, including foreigners from Nigeria, Pakistan, India and Zimbabwe as well as Indonesians, have been placed in isolation on a prison island where Jakarta carries out executions. Authorities stepped up preparations, with ambulances seen transporting coffins over to the island and cars heading for the penal colony in the evening carrying convicts' relatives, police and religious counsellors. President Joko Widodo believes Indonesia faces an emergency due to rising drugs consumption and has dramatically escalated the use of capital punishment, putting to death 14 drug convicts, mostly foreigners, since he took power in 2014. Indonesia last carried out executions in April 2015 when it put to death eight drug convicts, including two Australians, sparking international outrage. Family members say they have been told the convicts in the forthcoming round will be executed on Thursday night, according to a lawyer and diplomat, a day earlier than had originally been expected. The government could not be reached for comment. UN Secretary-General Ban Ki-moon led international condemnation, urging Widodo to halt the imminent executions and declare a moratorium on the use of the death penalty. Ban recalled that under international law, the death penalty should be used for the most serious crimes and said "drug crimes are generally not considered to meet this threshold." The UN High Commissioner for Human Rights has called on Indonesia to end the "unjust" use of the death penalty and the European Union has also urged a halt. But Indonesian foreign ministry spokesman Arrmanatha Nasir defended the upcoming executions as "pure law enforcement." There have been concerns about legal irregularities in the cases of some facing imminent execution, with Amnesty International citing "systematic flaws" in several trials and noting a handful of clemency appeals were still pending. These included Pakistani Zulfiqar Ali, whom rights groups say was beaten into confessing to the crime of heroin possession, leading to his 2005 death sentence. Rights group the Justice Project Pakistan say that the 52-year-old father of six was "tortured relentlessly" during a three-day interrogation in a house by police, after which he required surgery. Indonesian woman Merri Utami, who was caught with heroin in her bag as she came through Jakarta airport, claims she was duped into becoming a drug mule, and that police forced her into confessing with beatings and sexual harassment. Rights groups have mounted a campaign to save her, and 10 women's rights activists were detained by police Thursday in Cilacap — the port city closest to the prison island — as they rallied in support of her. Family members of Michael Titus Igweh, a Nigerian prisoner, also protested his looming execution, saying his case was still under review. "I don't think this is fair. They should fulfill his legal rights first," Igweh's sister-in-law Nila, who gave just one name, said in the port city. Support for the death penalty in Indonesia is generally high but there has been some public opposition. Dozens of protesters held a vigil late Thursday in front of the presidential palace in Jakarta, arranging candles in the shape of a noose and laying posters emblazoned with a bloody hand and the words "stop the executions" on the ground. Diplomats and lawyers were angered after authorities notified family members the executions would take place on Thursday, saying they believed they could only be held on Friday after the end of a legally required, 72-hour notice period. Authorities have not released a detailed list of the convicts who will face the firing squad but the Jakarta-based Community Legal Aid Institute said the group consists of four Indonesians, six Nigerians and one each from Pakistan, India, Zimbabwe and South Africa. Indonesia had an unofficial moratorium on the death penalty between 2008 and 2012 but resumed executions in 2013 under Widodo's predecessor, Susilo Bambang Yudhoyono.