A historically strong earthquake struck off Cuba’s northwest coast on Monday, according to official reports, shaking parts of Cuba, Mexico and Florida that are typically not prone to quakes.The US Geological Survey (USGS) measured the quake at a magnitude 6.1 at a shallow depth of 26km (16 miles) and its epicentre 104km west-northwest of Mantua, Cuba, about two to four hours by car from the capital Havana.Monday’s earthquake was unusual for this area of the Caribbean, said Paul Earle, a...