A ban on laptops and tablets in cabin baggage on flights from Turkey and some countries in the West Asia and North Africa to the US and UK has come into effect. <br/><br/>Officials said, devices larger than a smartphone must travel in the hold because of an increased risk that they could contain explosives. The US ban covers eight countries, while the UK restrictions apply to six. <br/><br/>Nine airlines from eight countries – Turkey, Morocco, Jordan, Egypt, the United Arab Emirates, Qatar, Saudi Arabia and Kuwait – are affected by the US ban. They operate about 50 flights a day to the US.