Nigeria and Sierra Leone have both withdrawn from the Summer Youth Olympic Games in Nanjing because of the outbreak of Ebola in West Africa.
Sierra Leone were the first country to reveal that they had pulled out following pressure from the Chinese authorities.
A few hours later they were joined by Nigeria, who withdrew their team in protest at how they had been treated in China.
"Nigerian athletes were quarantined, isolated and barred from training alongside athletes from other countries since they arrived the competition venue over news of Ebola virus in Nigeria," said Gbenga Elegbeleye, director general of the National Sports Commission.
"Following this discrimination, we have resolved to pull out from the Games."
The Nigerian delegation are believed to be making plans for their team of 12 athletes, who were due to compete in athletics, beach volleyball and wrestling, to return home.
More than 1,000 people have died in an Ebola outbreak in West Africa that has touched Sierra Leone, Guinea, Liberia and Nigeria.
It is not clear whether Guinea and Liberia will also be forced to withdraw.
National Olympic Committee of Sierra Leone President Patrick Coker claimed that the Chinese Embassy in the capital Freetown had warned them that their delegation "might find themselves in a troubled and awkward situation once they get to China's port of entry".
The delegation of 10 athletes and officials had already set-off on Monday (August 11) for Nanjing, where the Games are due to open on Saturday (August 16), when they were ordered to return home while still in transit.
They are now back in Freetown.
"Because of the prevailing Ebola Crisis in the [African] Sub-Region, the National Olympic Committee of Sierra Leone was advised by the Chinese Embassy in Sierra Leone and the Ministry of Foreign Affairs that the delegation for Nanjing should return," said Coker.
Among those who will miss out on the chance of competing in Nanjing will be the boys' volleyball team who had qualified to represent Africa in the Games.
Sierra Leone had also been due to compete in swimming and weightlifting.
The team's Chef de Mission, Unisa Deen Kargbo, who had already arrived in Nanjing yesterday ahead of the rest of the delegation is being forced to undergo a body temperature check every two hours, claimed Coker, to ensure that he has not contracted the virus.
He is being returned home tomorrow, said Coker.
The outbreak has also forced qualifiers for the Africa Cup of Nations to be moved from the affected countries.
The Chinese customs authority announced new measures yesterday to try to ensure that Ebola did not enter the country.
These included implemented stricter inspections on inbound flights from regions affected by Ebola and step up sanitary measures on incoming planes and goods.
Customs and quarantine staff members are also closely monitoring body temperature of passengers arriving at Lukou International Airport in Nanjing, capital of East China's Jiangsu Province.
Chinese authorities claim they are prepared for any cases that they encounter.
"We have done training with doctors in all arenas and designated hospitals," Huo Xiang, a spokesman for the Jiangsu Centre For Disease Control, said.
"This disease is not contagious when it's during incubation period, so there's no need for panic,"
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