Bulgarian air space closed on Sunday April 18
All air traffic over Bulgaria was halted at 9am on April 18, the Bulgarian Transport Ministry has announced.The Transport Ministry also said that all air traffic would cease until at least 9.15pm on April 18 as volcanic ash, which can prove a deadly hazard to flight engines, floated south over Bulgaria.Millions of stranded travellers face further air chaos as the volcanic ash from Iceland that has closed most of Europe's airspace continues to spread.About 20 countries have now closed their airspace and some have extended flight bans into Monday April 19. Experts say the cloud may not shift until later in the week.As of April 18, the following countries have closed their airspace: Austria, Belgium, Bulgaria, Czech Republic, Denmark, Finland, France, Germany, Ireland, Latvia, Luxembourg, Netherlands, Poland, Slovakia, Sweden, Switzerland and the UK.Flights are operating in Greece, Portugal, Russia, Turkey and Ukraine but even in these countries there is widespread disruption because many of the flights due to take off and land were heading to, or coming from, countries that have closed their airpsace.