Five years after Ken Saro-Wiwa was executed, his brother Owens Wiwa and Andy Rowell find Ogoniland under threat. As the fifth anniversary of the hanging of the Ogoni leader and environmentalist Ken Saro-Wiwa approaches on November 10, tension is once again rising in the Niger delta, as Shell attempts to return to Ogoniland, after an absence of seven years.

It is a move vehemently opposed by Mosop - the Movement for the Survival of the Ogoni People - of which Saro-Wiwa was president. In April this year its congress announced that Shell, which announced record £2bn profits last month, could enter Ogoni only to remove its remaining facilities, not restart them.

Despite this, Shell announced last month that it wanted to reactivate its 125 oil wells in Ogoniland. Bobo Brown, Shell's PR manager in Nigeria, said that there was also a "need to halt the pollution of the area, caused by the emitting of poisonous gases into the environment from leaking oil wells."

"We do want to get back into Ogoni," confirms Dave Stewart, a Shell spokesperson in London, "but only when everyone is in full agreement". This seems unlikely in the short term. In the five years since his execution, the protests that Saro-Wiwa and Mosop started have spread to other communities, spurred on by the grim reality of everyday life in the delta.

For millions of people, there is a daily struggle to gain access to basic necessities such as clean water, health care and education. "Ogoni people still languish in poverty, deprivation, marginalisation and environmental devastation," says Mosop.

In contrast, in affluent north America and Europe, Shell has been trying to rebuild its tarnished image. It launched its "profits and principles: is there a choice" PR campaign, highlighting its commitment to environmental issues and human rights.

The double page adverts are slick. As a beautiful African face stares out at you, the ad says: "None of Our Business? Or the Heart of Our Business: Human Rights. It's not the usual business priority. At Shell, we are committed to support fundamental human rights ... We invest in the communities around us to create new opportunities and growth."

"When Shell says that it respects human rights I do not believe them," responds Ike Okonta, from Environmental Rights Action, the Nigerian Friends of the Earth. "You cannot devolve the environmental wellbeing of a people from the general conception of human rights. Right now in the delta, everything Shell does by way of oil exploration leads to devastation of the environment. Shell still works with the Nigerian government to make sure that the local people, who are trying to restore their farmlands, don't stand up and protest."

Whatever position Shell takes it is working with a government that has been brutal in protecting its oil interests. For example, this year also sees the 10th anniversary of the "massacre" of Umuechem. In October 1990, the Etche community of Umuechem protested against Shell. At the threat of the demonstration, Shell called in the notorious Mobile Police Force.

Eighty people were killed and some 495 homes destroyed. Although the official inquiry blamed the police for the incident, the community's frustration with the company was clear in their evidence, complaining that Shell's drilling operations had "had serious adverse effects" and that their farmlands were "covered by oil spillage/blowout and rendered unsuitable for farming".

Umuechem was a chilling precursor to the military backlash unleashed against protesters over the next decade. When the Ogoni mobilised in 1993, with Ken Saro-Wiwa leading the grassroots rebellion, 2,000 people were killed, with an estimated 80,000 made homeless in the next couple of years. Despite the threat of violent retaliation, the neighbouring Ijaw community mobilised in 1998, the same year that the reviled General Sani Abacha died. Many saw the passing of Abacha, who had defied world opinion to sign Saro-Wiwa's death warrant, as a welcome step. However, Human Rights Watch reported "human rights abuses in the oil producing communities continue and the basic situation in the delta remains unchanged".

By December 1998, Ijaw activists had adopted the "Kaiama Declaration", which demanded an end to oil production in their area. "We are tired of gas flaring, oil spillages, blowouts and being labelled saboteurs and terrorists," said the declaration. The military crackdown was both predictable and brutal. There were deaths of "possibly over 200 people; the torture and inhuman treatment of others; and the arbitrary detention of many more", recorded Human Rights Watch. Girls as young as 12 were raped or tortured.

They also documented how the Nigerian military destroyed Odi, a town of 15,000 in Ijawland in November 1999, demolishing every building, except the bank, the church and the health centre. Hundreds of unarmed civilians were killed. "When I went back in March I saw a town I used to know razed to the ground," says Okonta. "Everything was burnt down. There was still the smell of rotting flesh. It was cold-blooded murder of old men and women".

Despite the continuing violence, the appointment of a civilian government, headed by former military head of state, Olusegun Obasanjo, in May 1999, had given new hope to Saro-Wiwa's family that his body might be released for burial. Their hopes were raised the following month when the new president gave permission for the remains to be released. In February 2000, forensic experts flew [with Owens Wiwa] to exhume the body. However, at the last minute the government refused to give access to the grave.

A symbolic burial for Saro-Wiwa, according to the Ogoni tradition, was held instead in April. Placed in his coffin were two of his favourite novels and his pipe, requests that he had made in his will. Over 100,000 Ogonis attended ceremonies in the week-long events to mark the occasion.

The family feels that the reason the authorities blocked the burial is that, under the Nigerian legal system, if they had given his body back then it could be interpreted as an official acknowledgement that Saro-Wiwa was innocent. This could hamper Shell's defence in the legal action the family is taking against the company in New York. Shell has said that the case should be dismissed as Saro-Wiwa was a convicted murderer.

Undeterred, the Saro-Wiwa family wrote to Obasanjo last month: "We are concerned that Ken Saro-Wiwa is still regarded as a criminal in the Nigerian statute books despite the fact that independent observers, including a UN fact-finding team, have questioned the fairness of the tribunal that sentenced him and the legality of his execution." They therefore requested "that you exonerate him of the wrongful conviction of murder". The president has yet to reply.

But the signs are not good. The violence and collusion continue. Last month, according to the Ijaw National Congress, 10 activists were killed protesting against the Italian oil company, Agip. Also last month, Obasanjo nominated the ex-deputy managing director of Shell in Nigeria, Godwin Omene, to head the new Niger Delta Development Commission. If Omene's appointment is approved, which looks likely, it will be a severe blow to the communities who had thought an independent development organisation might assist their plight.

"Godwin Omene is from the delta and we believe he would have the interests of the delta at heart and would try and make sure that a fair share of oil revenues would be put to use developing the region," says Dave Stewart from Shell.

"It is very true that those in the delta have a very different life from other oil regions such as Norway or the UK. But what can we do about it? We could say its the government's responsibility, but we don't," said Stewart. "In the last year we spent $50m on community developments. This year we will spend more."