Powerful earthquakes struck Venezuela on Wednesday afternoon, toppling buildings in the capital Caracas, trapping people in the rubble and prompting scientists to warn of potentially heavy casualties and widespread destruction. A magnitude 7.2 earthquake hit about 160km (100 miles) west of Caracas, followed less than a minute later by a magnitude 7.5 tremor, according to the US Geological Survey (USGS). “High casualties and extensive damage are probable and the disaster is likely widespread,”...