Heavy rain in parts of Germany has caused flooding that inundated streets and led to dozens of flight cancellations at country's busiest Frankfurt airport.<br />'' <br />''Local media reported, the storm swept over southwest Germany yesterday evening, dumping huge quantities of water and reportedly unleashing lightning for about an hour.<br />'' <br />''Frankfurt airport spokesman today said, it was forced to cancel 90 flights while 23 more were re-routed to land at other airports. Some passengers slept on camp beds while many spent the night at the airport hotel.<br />'' <br />''The fire service said, it launched more than 500 operations from yesterday evening to today morning related to the storm.<br />'' <br />''It said, streets, cellars and lower-lying residential areas were rapidly flooded, while trees toppled over, hitting vehicles. The storm also affected other areas, with Gelsenkirchen, in the region North Rhine-Westphalia, hard hit.<br />'' <br />''<span style="color: #222222;">Emergency service workers rescued people from vehicles at several highway underpasses.</span><br />