Oil prices tumbled more than $3 a barrel on Monday amid geopolitical tensions in the Middle East. Both Brent and US West Texas Intermediate crude futures hit their lowest levels since Oct. 1 at the open. Brent was at $72.88 a barrel, down $3.17, or 4.2%, while WTI slipped $3.13, or 4.4%, to $68.65 a barrel. The benchmarks gained 4% last week in volatile trade amid rising geopolitical tensions. Source: Qatar News Agency