NAIROBI (Reuters) -Kenya Airways on Saturday warned its striking pilots they could be dismissed if they do not return to work immediately as industrial action led to the cancellation of dozens of flights and left thousands of passengers stranded. The pilots at one of Africa’s largest carriers downed tools from 6 a.m local time on Saturday, affecting business and leisure travellers at one of Africa’s most important aviation hubs. In an internal memo to pilots seen by Reuters, the carrier said the strike was illegal and asked pilots to return to duty immediately. “This (strike) has resulted in m…