Myanmar received recognition from the international community for democratic reforms that began in earnest with general elections in 2010. The country's human rights record, however, remains a top concern for campaigners.
Save the Rohingya founder Jamila Hanan told Oil Change International there was a "definite link" between oil development and conflict involving ethnic Rohingyas.
She said a pipeline planned to southwest China is part of the problem.
"We are anticipating a third massacre of the Rohingya on the same scale which took place in Rwanda," Hanan said. "We have been informed that this will take place sometime between now and mid-April."
The United Nations estimates that conflict between Rohingyas and Buddhist in the region last year left at least 76 people dead and tens of thousands of people displaced.
International investors are examining business opportunities in the Myanmar energy sector as world governments ease sanctions on the country because of political reforms. The China National Petroleum Corp. said it expects to start moving oil and natural gas through pipelines in Myanmar as early as June.
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