Oil tumbles as much as 2% as Oklahoma crude piles up

Oil prices fell more than 2% on Monday.
Data showed inventories at the US crude delivery hub rose last week.
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Oil prices slid Monday after inventories at a key US crude delivery hub jumped last week, adding to demand concerns.
West Texas Intermediate was down 0.6% to $67.34 per barrel at 3:15 p.m. ET. Brent, the international benchmark, shed 0.3% to $72.74 a barrel. Both had fallen more than 2% in midday trading.
Market research firm Genscape data showed invento