The UN has warned that West Africa is the new route for cocaine smugglers
Police in Sierra Leone have arrested at least eight foreigners after seizing a plane loaded with cocaine at an airport outside the capital.
The plane bore a fake Red Cross logo, reports said.
The 600kg cargo, worth an estimated $54m, was abandoned on the runway shortly after arriving in the dark in the early hours of Sunday.
The BBC's Umaru Fofana, in Freetown, says the pilots had fled in a vehicle that drove through the perimeter fence.
Our correspondent says it was a dramatic and daring escape, but they appeared to experience no resistance from security at the airport.
Police spokesman Francis Munu said that a small white aircraft with a fake Red Cross emblem had landed at Freetown's international Lungi airport without authorisation.
"When police searched the aircraft, some 600kg (1,320lb) of cocaine was discovered along with gallons of fuel and several AK47 and AK48 rifles were discovered with 339 rounds of cartridges," he told AFP news agency.
The spokesman said roadblocks were set up and police later arrested seven foreign nationals - three Colombians, two Mexicans, a Venezuelan national and a US citizen - in a car 10km (six miles) from the airport.
On Monday they arrested an eighth foreigner, described as being "of Cuban-American origin", AFP said.
However, another report said that nine foreigners had been arrested.
A number of Sierra Leonean nationals had also been detained for questioning, reports said.
The incident comes after a warning from the US embassy in Freetown that some members of the police in Sierra Leone were working with organised criminals, our reporter says.
The seized drugs are now with the United Nations and the British-led International Military Advisory Training Team.
Michael Schulenburg, the head of the United Nations mission in Sierra Leone, said it was a very big seizure.
"It's drawn attention to the fact that we have to do more. There must be many more flights like this. It's something that governments can lose control over," he told Reuters news agency.
Last month, the UN warned that West Africa was under attack from international gangs seeking new routes to smuggle cocaine from South America to Europe.
After years of war, Sierra Leone is one of the world's poorest countries and corruption is a major problem.
Guinea-Bissau, another weak West African state, has also been targeted by Latin American drugs cartels.