The internal state security memorandum, which is marked "restricted" 12 times, says that regular financial "inputs" from oil companies had been discussed. A British environmentalist said yesterday that the author of the document had told him that his men had been paid by Shell to protect installations.
Other confidential documents indicate that Shell asked for armed "assistance" against local demonstrators. And a leading Nigerian yesterday accused the company of "militarising commerce in his country".
Shell admits asking for help from armed police but strenuously denies paying the military. It says that there have been instances where the Nigerian authorities have "gone too far" and insists that it "does not wish to operate behind military shields".
But the disclosure of the documents will greatly increase the international row that has followed the execution of the writer and environmentalist, Ken Saro-Wiwa, and eight fellow Ogoni activists last month, and will step up pressure on the multinational company to leave Nigeria.
The memorandum, headed "Law and Order in Ogoni etc" and dated 12 May 1994, is to the Military Administrator of Rivers State from the Chairman of Internal Security, Major Paul Okuntimo. It notes: "Shell operations still impossible unless ruthless military operations are undertaken for smooth economic activities to commence."
Under the heading "recommendations/strategies" Major Okuntimo lists "wasting operations during MOSOP and other gatherings making constant military presence justifiable". (MOSOP is the Movement for the Survival of the Ogoni People to which Ken Saro-Wiwa belonged).
He goes on to recommend: "Wasting targets cutting across communities and leadership cadres especially vocal individuals" and "wasting operations coupled with psychological tactics of displacement/wasting as noted above."
Under the heading "financial implications (estimates/funding)" the memorandum lists "pressure on oil companies for prompt regular inputs as discussed". Major Okuntimo estimated that there would have to be an "initial disbursement of 50 million naira as advanced allowances to officers and men, and for logistics to commence operations with immediate effect, as agreed".
Yesterday Nick Ashton-Jones, a British environmentalist, said that Major Okuntimo had told him and a Nigerian lawyer, Oronto Douglas, in June 1994 that he was carrying out his operations for Shell and that he was unhappy because the company had stopped paying his men. Mr Ashton-Jones, who says he was arrested by Okuntimo and beaten on his orders, said that the remark "had stuck in our minds because this was something that we had suspected".
He says that he has no real doubt that the company had been paying the major, but this remark is the only evidence he has for it.
Shell said yesterday that it was compelled by law to inform the authorities when there was a threat to oil installations and that it only called in the police when its facilities or staff were at risk. It agreed there had been "instances where the response by the authorities has gone too far with tragic consequences", but added "the level of response that a country's authorities carry out ... has got to be a matter for those authorities."
The company added: "We categorically refute that any form of input was ever provided to the military, neither would we do so if approached on such a matter.
"At the end of the day dialogue and cooperation and goodwill between people is the only way forward."