DAKAR/BANJUL (Reuters) - When 52 West African migrants sneaked into Gambia from Senegal on July 21, 2005, they expected to meet a boat to ferry them to Spain, but instead they were arrested and put to death on the orders of then-president Yahya Jammeh.

FILE PHOTO: Gambia's President Yahya Jammeh, who is also a presidential candidate for the Alliance for Patriotic Re-orientation and Construction (APRC) attends a rally in Banjul, Gambia November 29, 2016. REUTERS/Thierry Gouegnon/File Photo

Jammeh, in power for more than two decades until he fled into exile earlier this year, had feared the migrants were mercenaries come to overthrow him.

Two days after their arrest, eight of them were found shot dead in a beachside bird reserve 20 miles (32 km) southwest from where they had been detained. The bodies of at least 40 others were dumped down a well in neighboring Senegal.

The account is just one of many harrowing tales revealed by an ongoing investigation into suspected atrocities ordered by President Adama Barrow, who defeated Jammeh in an election last December.

Jammeh initially refused to concede defeat but fled into exile in Equatorial Guinea in January after West African regional body ECOWAS threatened to remove him from office.

Reuters was unable to verify the accounts from witnesses and investigators it interviewed, but if confirmed, the findings are likely to revive calls for Jammeh to be brought to justice.

They will also become part of an already contentious Truth and Reconciliation Commission this year that is meant to bridge a bitter divide between Jammeh supporters and his victims.

“A successful Truth and Reconciliation Commission process will not only see the truth come out, but should also be designed to provide the basis for criminal investigations and prosecutions,” said Steve Cockburn, Amnesty International’s deputy regional director for West and Central Africa.

Jammeh, who made headlines as president for such quirks as claiming to have a herbal cure for AIDS and vowing to rule for a billion years, could not be reached for comment. He has denied any wrongdoing since coming to power in a 1994 coup.

“BODIES SCATTERED EVERYWHERE”

Gambian intelligence officials had received word in early July 2005 of a plot by mercenaries from Burkina Faso to overthrow Jammeh, said Pa Jallow, a retired police officer who was in charge of arresting the migrants.

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The men were in their early twenties, unarmed, their pockets filled with small amounts of euros and dollars, he said.

“They looked so tired, confused and dejected. Most of them weren’t even wearing shirts. I immediately thought these people are migrants, not mercenaries,” Jallow told Reuters.

After their arrest, Jammeh’s elite guard, called ‘junglers’, came to the house where they were being held and took them away in small groups, said one police source who was present.

“The junglers would come and take three, four, five at a time. They never returned,” the source said.

Another former police officer involved in the arrests, who spoke to Reuters on condition of anonymity, witnessed a group of junglers shoot dead eight of the migrants in the bird reserve.

“The junglers told the Ghanaians to run into the forest, and they shot them dead. There were bodies scattered everywhere,” he said.

Some of the junglers have attested that they carried out the killings on Jammeh’s orders and dumped most of the bodies in a well across the border.

In a separate incident, six men accused of an attempted coup in March 2006 were shot and thrown down the same well as the migrants, two police sources said. In 2012, nine death row inmates were strangled and dropped down a different well, according to testimony given to police.

In total, at least 60 people - including the 40-odd migrants - were killed and dumped in two different wells during Jammeh’s rule, according to testimony provided to the investigators and by the Jammeh-era police officers interviewed by Reuters.

Others were buried in shallow graves that have been discovered since Jammeh left power.

Locating the bodies has proven difficult.

The entrance of one well in Kanilai, near Jammeh’s old compound, has been cemented over. The other well, in Senegal, is in an abandoned village in an area peppered with landmines laid by Senegalese Casamance rebels.

Gambia’s Solicitor General Cherno Marenah said he had not yet seen a formal report on the investigations, adding that some wells had been secured by the military but not yet searched.