DUBAI—Dubai-based Dodsal Group said on Monday that it has discovered gas reserves worth an estimated $8 billion in Tanzania, which could help lift the eastern African nation’s economy.

The family-owned conglomerate said it struck 2.7 trillion cubic feet of natural gas deposits at a field in the Ruvu Basin which is located about 50 kilometers west of the country’s largest city, Dar es Salaam. It began exploring the site in 2009, two years after obtaining the concession rights there.

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