A former Argos security guard who worked in the store on London's Holloway Road has been elected president of Gambia.

Now the country's opposition leader, Adama Barrow today said he was expecting a phone call from President Yahya Jammeh conceding defeat in Gambia's election.

Barrow said he was still waiting for an official result from the electoral commission but that his own count showed he had won the poll.

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Former Argos security guard Adama Barrow has won the Gambian presidential election

Dictator Yahya Jammeh vowed to rule his country for 'a billion years', but has now been toppled by his unlikely rival.

Jammeh, a friend of Libya's late Colonel Gaddafi, ruled the west African state of Gambia through a bizarre personality cult of witchcraft and brutality.

He claimed to have invented his own herbal HIV 'cure', and was once accused of force-feeding hallucinogenic potions to an entire village of people he thought had bewitched his aunt.

The man who styled himself 'Excellency Sheikh Professor Doctor President' has been defeated by Mr Barrow, who spent his early years tackling shoplifters at the Argos store.

Mr Barrow studied property management in London before becoming the leader of Gambia's official opposition

Now a successful estate agent in his home country, the quietly-spoken Mr Barrow was one of the few Gambians brave enough to take Mr Jammeh on in the contest.

Mr Barrow's victory comes despite Mr Jammeh's ministers making fun of him over his days doing low-level security work in London.

At a pro-government rally ahead of the elections, Sheriff Bojang, the Gambian information minister, told the crowd sarcastically: 'We have heard that Mr Barrow worked as a security guard in ... what is it... this shop called Argos in Britain?'

Lamin Cham, Mr Barrow's spokesman, said that the opposition leader would go to State House in the capital, Banjul, to be officially declared victor at 5pm today.

'It's game over,' he told the MailOnline.

Like Zimbabwe's Robert Mugabe, Mr Jammeh describes any criticism of him by Western governments as 'neo-colonial' lecturing.

He is particularly scathing of Britain, and at a recent campaign rally attended by the Mailonline, declared that Britain had done 'nothing' for Gambia during '400 years of colonialism'.

Gambia's dictator president Yahya Jammeh is expected to concede defeat later today

His claims were dismissed as posturing by Mr Barrow, who said that he owed his career success to his tough years in Britain, where he lived and studied property management between 1998 and 2002.

During that time he paid his rent with security jobs in offices, music festivals and high street stores, once tackling a shoplifter at Argos who was jailed for six months.

He also lived on a crime-plagued housing estate in Kidbrooke in south-east London, which has since been demolished.

'My time in Britain taught me the importance of working hard and good time-keeping, and both those things helped me a lot when I went back home,' said Mr Barrow, 51.

Voters queue at a polling station in Banjul yesterday. There are fears the suprise result could leave to violence in the country if President Jammeh refuses to accept defeat

'People think life is easy in Europe, but it can be a tough place to make your way in as a visitor.'

A nation of just 1.9m people, tiny Gambia is best known in the West as a winter sun destination, attracting 100,000 foreign tourists every year to its pristine Atlantic beaches.

Britons make up around half the visitors, with thousands also living there in retirement.

Since taking power in a military coup in 1994, 51-year-old Mr Jammeh has won four elections, most of which have been marred by accusations of cheating.

Critics say he ruled by decree, with anyone who disagrees with him liable to end up in the notorious Mile Two prison, which is not far from the main tourist beaches in the capital, Banjul.

In April, several opposition figures in Mr Barrow's United Democratic Party were thrown in jail, and another two fatally beaten in custody.

Jammeh, a friend of Libya's late Colonel Gaddafi, ruled the west African state of Gambia through a bizarre personality cult of witchcraft and brutality

In a subsequent speech, Mr Jammeh snarled: 'Let me warn those evil vermin called opposition. If you want to destabilize this country, I will bury you nine-feet deep.'

In 2012, he scrapped a moratorium on the death penalty and executed nine inmates at the prison by firing squad, telling human rights groups to 'bite their own nose'.

While he claimed it was because Gambia was facing a crime wave, rumour had that it a fortune teller had said a 'human sacrifice' was necessary to ward off a coup attempt.

Rather like North Korea's Kim Jong-un, Mr Jammeh was quick to upbraid any official who displeased him.

However, his aggression backfired by galvanising Gambia's normally quarrelsome opposition factions to unite around Mr Barrow.

As part of his anti-Western crusade, Mr Jammeh pulled Gambia out of the Commonwealth in 2013, saying it was a 'neo-colonial institution', and dropped English as an official language, even though it is still widely spoken in Gambia.

Mr Barrow said that he owed his career success to his tough years living in Britain

Last month, he also withdrew Gambia from the International Criminal Court, describing it as the 'International Caucasian Court'. He had demanded that the court prosecute European nations for failing to rescue African migrants crossing the Mediterranean - a large number of whom are Gambians seeking a better future.

'These are desperate moves that don't help Gambia at all,' said Mr Barrow. 'The only reason he left those organisations is because they expect him to practice good governance. If we are elected we will restore Gambia's relations with the outside world, and rejoin both the Commonwealth and the ICC.'

There are fears that Mr Jammeh may not go quietly. In the event of violence escalating, Britain could face calls to send troops in as peacemakers, according to Yanks Darboe, a London-based Gambian activist.

Mr Darboe said the operation would be comparable to that carried out by France to quell the Islamist uprising in neighbouring Mali in 2013.

'If there was trouble, a lot of Gambians would like to see Britain come to help, as they don't think the neighbouring African leaders would do much.