An Air India flight to London returned to Delhi today after an unruly passenger allegedly harmed two cabin crew members, the airline has said. The flier has been deboarded and a police case registered. The shocking incident comes months after a drunk man urinated on a woman co-passenger onboard an Air India plane flying from New York to Delhi. The episode, which came to be known as Pee-Gate, had sparked a massive debate on passengers' conduct, prompting airlines to issue tough guidelines to tackle unruly fliers.