Story highlights Saudi prince detained on suspicion of drug smuggling in Lebanon, security source says

Prince was among five Saudis arrested at Beirut's airport, Lebanon news agency says

They're accused of trying to transport 2 tons of amphetamines, agency says

(CNN) A member of Saudi Arabia's royal family was detained at the Beirut, Lebanon, airport over an alleged attempt to smuggle drugs out of the country on a private plane, a security source told CNN.

The prince was among five Saudi nationals arrested Monday after being accused of trying to transport 2 tons of Captagon amphetamine pills onto a plane bound for Saudi Arabia, according to the official Lebanese National News Agency.

It was the largest drug bust ever conducted at the Beirut-Rafik Hariri International Airport, the news agency reported.

What's Captagon?

The U.N. Office on Drugs and Crime says that amphetamines are the most prevalent type of drug used in Saudi Arabia and that reports of amphetamine seizures in the Middle East "refer predominantly to tablets bearing the Captagon logo."