The evil that men do live long after them, it is said.

In 1995, the military regime of Sani Abacha executed 9 Ogoni men in Niger Delta who were protesting the activities of oil companies in the region.

22 years after, widows of four of the nine men have filed a civil lawsuit seeking compensation and an apology from Royal Dutch Shell.

They allege that Shell was complicit in Abacha’s military crackdown, providing support to the military which ultimately led to the executions of the men known as the Ogoni 9.

This is according to a court summon filed in a court in The Hague, Netherlands.

The four widows' civil case was filed by human rights law firm, Prakken d'Oliveira with the support of Amnesty International on behalf of Esther Kiobel, Victoria Bera, Blessing Eawo and Charity Levula.

The summon did not specify how much compensation they are seeking.

"Shell and the military regime formed an alliance in the events leading to the deaths of the Ogoni 9.

"Their relationship was one of mutual dependence: the Nigerian state was dependent on the income from oil that Shell generated; in turn, Shell was dependent on the benevolence and protection of the regime to pursue its activities in Nigeria and in this way realise a substantial part of its turnover," the summon said.

But Shell, the largest oil producer in Nigeria, has repeatedly denied any involvement in the executions of the 9 men or the government's response to the unrest.

"We have always denied, in the strongest possible terms, the allegations made by the plaintiffs in this tragic case," Shell said in a statement.

"SPDC (Shell Petroleum Development Company of Nigeria) did not collude with the authorities to suppress community unrest and in no way encouraged or advocated any act of violence in Nigeria. In fact, the company believes that dialogue is the best way to resolve disputes," the statement added.