While South Africans were enjoying the 1 May Workers' Day public holiday, something extraordinary was unfolding in Port Elizabeth.
Something with far-reaching implications for international human rights and for international trade, a novel legal situation highlighting the plight of a little-remembered, embryonic state - Africa's last colony, the Western Sahara.
Early that morning, the ship, N M Cherry Blossom, arrived at Coega, the specialised port on the outskirts of Port Elizabeth, to take on fuel.
Its cargo was phosphate worth about US$6m, bound for New Zealand. That much was clear. But just who owned the cargo is a much tougher question and one that the courts here have been asked to resolve.
The night before the Cherry Blossom arrived, the Saharawi Arab Democratic Republic (SADR) and the Polisario Front had brought an application before Judge Elna Revelas. They asked for a temporary order to keep the ship's cargo in the area of the court's jurisdiction and for the sheriff to attach the cargo pending the outcome of their action.
She granted the temporary order, subject to a confirmatory affidavit being filed once it arrived in South African territorial waters, and set 18 May for a full hearing on the disputed order. Through the night, as the Cherry Blossom closed in on the crucial 12 nautical mile zone off the South African coast, Polisario members all round the world, along with their lawyers in South Africa, were all watching its progress on their computers.
Once the ship arrived, it was a comparatively simple matter to serve the order. But come 18 May, when the question of confirming the order was argued, a specially constituted full Bench of the High Court presided, given 'the novelty of the matter and the complexity of the international law issues' involved.
Last Thursday those three judges delivered their decision: they approved the order that the sheriff attach and hold the cargo in Port Elizabeth and remove the ship's registration documents and trading certificates.
However, the order provides that, if appropriate security is put up, the cargo would be allowed to continue its journey.
Now the SADR and Polisario have a month to issue summons for the return of the cargo, failing which the order lapses. Once summons has been issued, the dispute is likely to feature on the court rolls in South Africa for years ahead, with possible applications and appeals even before the hearing about ownership of the cargo.
There is no dispute that the phosphate comes from the Boucraa mine in the northern part of Western Sahara. That mine is operated by Phosboucraa, a Moroccan company and a wholly owned subsidiary of OCP, another Moroccan company, the largest exporter of phosphate rock and phosphoric acid, and producer of fertiliser extracts, in the world.
But why is a Moroccan company mining phosphate in Western Sahara, its southern neighbour? Because Morocco claims the area as its own. And that is where the issue of Africa's last colony comes in.
From 1884, during the height of African colonisation and for nearly a century, this was known as Spanish Sahara. Polisario was formed to liberate the country and represent its people. In 1976 Spain eventually pulled out, but not before offering its former colony - not to its own people, but to neighbouring Morocco and Mauritania. In the meantime, however, the Polisario had claimed the Saharawi Arab Democratic Republic as a sovereign state.
Although Mauritania has since abandoned its claim, Morocco holds much of the area in a military grip. Anticipating by decades US President Donald Trump's idea of a security 'wall', Morocco has built a rock and sand barrier three metres high and 2 700 km long across the desert. Some 80% of the country is on the western side of this berm, 'occupied' by Morocco. For additional security this part is controlled by 120 000 Moroccan troops, while literally millions of landmines are embedded in the sand around the length of the berm itself.
The question of the status of Western Sahara has proved intractable, with the United Nations so far unable to reach any finality. Key members of the Security Council have strong bonds with Morocco and appear reluctant to back self-determination for the region against the wish of their ally.
If this sounds familiar, you may be remembering pre-independence Namibia. After the Germans quit their former colony, it was 'colonised' by its neighbour, South Africa, and for a long time that neighbour-coloniser tried to hold on in the face of world disapproval.
Instead of a berm, however, South Africa waged a more conventional war to maintain its hold. Just as the war in Namibia was complicated by international politics and the cold war in particular, so is the situation in Western Sahara complicated by international terrorism with a number of security reports warning that disaffected refugees from Western Sahara are easy prey for extremists.
Seen against this background the phosphate cargo becomes almost a symbol. It was mined by a Moroccan company, operating in land that Polisario describes as unlawfully 'occupied' by Morocco. Polisario says the area's mineral wealth belongs to the SADR, not Morocco, and money from the sale of the phosphate belongs to the people of the land where it was mined.
That question - to whom does the phosphate belong? - is what the court has now agreed to consider. If to Western Sahara, then the mining company would have to relinquish the cargo. No one has suggested the phosphate belongs to Morocco. Perhaps the best alternative candidates might be the New Zealand company that has bought the fertiliser and that is stressing about the delay in arrival. But reports in the New Zealand media quote the buyers there, Balance Agri-Nutrients, as saying they have not yet paid for it and that the cargo still belongs to the mining company.
The fact that the full Bench decided South African courts could consider the dispute, and that the vessel must stay put pending that decision has infuriated OCP. It has declared its 'outrage', and 'denounces' and 'contests' the decision of the court which, in the view of the company, 'has no jurisdiction to rule' on the situation.
According to OCP, the court's decision disregards established international law principles and the ongoing UN process, and 'impedes international trade in South Africa'. The company also contrasts the Port Elizabeth decision to hear the case with a very similar case brought in Panama earlier this month, again by the SADR and Polisario, contesting ownership of a cargo. In that case, the judge declared the court had no jurisdiction to entertain the matter, a view that the company 'commends and welcomes'.
Back in Port Elizabeth, however, the full Bench quoted key findings of the International Court of Justice: Morocco has no claim to sovereignty over Western Sahara; it acquired control of the area by force, contrary to customary international law. The natural resources of a territory may only be exploited on behalf of its people 'if to do so will be for (their) benefit'. Yet OCP does not claim to have mined the phosphate 'with the consent of the people' of the territory, and 'they do not and cannot claim to do so on behalf of its people'.
As to the criticism that the court should not agree to hear the case because it affects the legal rights of Morocco, the judges say that Morocco did not assert any right or interest in the cargo. It was not a party to the case. If a South African court found that the company's exploitation of minerals was illegal this 'can have no effect upon the legal rights of Morocco'.
It's a fascinating judgment, important for the way it interprets the law and how it highlights a continuing international disgrace - the failure of both the UN (where Morocco is a member, but not Western Sahara) and continental bodies such as the African Union (of which both are members) to resolve the issue of the continent's last colony. There are even suggestions that the case could play a significant role in resolving the dispute because of the pressure it might put on the parties - and other world players - to focus on ending the stalemate.