Airport authorities in Zimbabwe impounded a US cargo plane after blood was seen dripping from the jet and millions of rand, South Africa’s currency, were discovered on board.

The MD-11 trijet owned by Florida-based Western Global Airlines was carrying a consignment for the South African Reserve Bank (SARB), the country's central bank, from Munich, Germany to Durban, South Africa.

The captain of the plane requested a technical landing at Harare International Airport in Zimbabwe for refueling, after initially having the same request rejected by authorities in Maputo, Mozambique.

Saudi prince arrested on private plane with 2 tons of drugs - reports https://t.co/R3MIDmz74Xpic.twitter.com/7lifnVZXcR — RT (@RT_com) October 26, 2015

After landing, airport staff noticed blood dripping from the airliner and while initially thinking it was that of a dead bird, a body of a dead man was actually discovered, Zimbabwe’s Herald newspaper reported.

"The jet crew was questioned and they said they hit a bird in the air. But then a search was made and the body of an adult male fell out," a source told African News Agency.

Warning Graphic Content: Corpse found in US plane in Zimbabwe https://t.co/2hU9CG3sGqpic.twitter.com/oFMb3nODK2 — thezimbabwenewslive (@thezimnewslive) February 15, 2016

The nationality of the deceased is not yet known but a police investigation is underway, with a spokesman for the South African Reserve Bank telling The Telegraph they believe the man "is presumed to be a stowaway."

AP report the man is thought to have sneaked onto the plane via the landing gear where his arm was severed when it contracted, splattering blood onto the plane’s fuselage.

In addition, "millions of South African rand" were also discovered on board and is reportedly being guarded by two SARB couriers. By current exchange rates, one million SA rand is worth $63,615.

The plane remains impounded at the airport and the SARB has said it is "working with the relevant authorities to ensure that the cargo is released and transported to South Africa".

READ MORE: Mugabe defies ’death prophets’ by living into 2016

The crew on board the plane consisted of two Americans, two South Africans and two Pakistanis, all of whom are currently being questioned by police.

Zimbabwe's Minister of Foreign Affairs Simbarashe Mumbengegwi has summoned the ambassadors of South Africa, USA, Pakistani and Germany for an emergency meeting over the issue, according to the Voice of America Zimbabwe radio service.

Zimbabwean aviation authorities last seized a plane in 2004 when British mercenary Simon Mann and 69 others were discovered on board a Boeing 727 with £100,000 ($144,423) worth of weapons and equipment in tow, to take part in what Zimbabwean officials said was an attempted coup.