PHOTO: An EasyJet Airbus A319. (photo via Flickr/TransportPixels)  An EasyJet flight traveling from Manchester, England to Tenerife, Spain was forced to make an emergency landing in Lisbon, Portugal over the weekend after three passengers were suspected of taking drugs mid-flight.According to The Sun, the flight was diverted after crew members discovered a substance thought to be cocaine in the toilet.The flight was met by Portuguese authorities in Lisbon who boarded the plane and arrested the men.MORE Airlines & Airports"In the first hour the crew saw three lads going to the toilet a lot," passenger Sophie Bennett told the Sun. "They checked and one of the crew came back with a bag. Over the next few hours, the lads got aggressive, swearing at the crew.""At one point one of the crew was crying because of stress."Bennett said passengers were only given a 10-minute warning for landing in Lisbon and were asked to stay seated while police took the men into custody. The Sun reported the men were arrested on suspicion of illegal activities on a flight. Tests on an envelope containing traces of a suspected illicit substance have so far proved inconclusive.EasyJet confirmed the incident and condemned the men's actions."The flight was met by police due to three passengers behaving in a disruptive manner," easyJet said in a statement. "We don’t tolerate abusive or threatening behavior."The men reportedly received a lifetime ban from the carrier, according to The Sun.READ MORE: Authorities Discover $434k Worth of Cocaine in Nose of American Airlines Plane The flight eventually reached its final destination in Tenerife at 1 a.m., nearly three hours behind schedule.The most recent incident comes just one week after an EasyJet pilot was accused of asking passengers to vote on whether to the plane was safe enough to fly. The airline denied the allegations, instead claiming the pilot asked passengers whether they wanted to remain onboard while the crew worked through a technical problem.Follow @_Pat_Clarke