The explosion happened Thursday afternoon at an administrative building in the Pemex office complex.

CNN: February 1, 2013 -- Updated 1937 GMT (0337 HKT)

The administrative building could double as a gallery of South African art, and the auditorium feels like a Broadway theater.

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Pemex, the powerful but much-criticized state oil company, has said it's not clear what caused the blast, which took place Thursday at an administrative building in the Pemex office complex in Mexico City.

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This includes everything from administrative laws concerning building to criminal statutes related to treason.

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It later confirmed that an explosion had taken place "in the B2 building of the administrative centre".

BBC: Mexico City blast at state oil firm Pemex kills 25

Still, gross profit declined 2%, principally due to increased building material costs and selling, general and administrative expense rose 14%, primarily due to investments in personnel and other expenses related to plans for growth, including the start-up of its Lexington, Ky.

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