Shell Petroleum Development Co. of Nigeria Ltd. said it shut down the Trans-Niger pipeline because of an explosion and fire at the point of the theft. Shell said it would reopen the pipeline once it was considered safe.
The company said output of about 150,000 barrels of oil per day is suspended because of the closure.
An opinion column published Sunday by Nigerian newspaper ThisDay said more danger lies ahead for the nation's oil sector because the government has failed to take the threat from oil thieves seriously.
Shell's regional director Mutiu Sunmonu said last week's incident in Ogoniland is a "sad reminder" of the state of affairs in Nigeria.
"Crude theft continues to pose significant challenges to the people, environment and the local and national economy, and all stakeholders must work together to stop this criminal activity," he said last week.
The Nigerian government says it is taking the matter seriously.
Nigeria ranks near the bottom in terms of production among members of the Organization of Petroleum Exporting Countries.