British authorities said they\u2019ve disrupted a "major terrorist plot" to blow up at least 10 passenger flights from the United Kingdom to the United States, The Washington Post reports.A full-scale security clampdown at U.S. and British airports caused a wave of delays and canceled trans-Atlantic flights, the article states. According to London\u2019s deputy police commissioner, Paul Stephenson, 21 suspects were arrested in London and Birmingham, England. It\u2019s believed that roughly 50 people are involved in the plot to destroy U.S.-bound flights on American Airlines, Continental Airlines and United Airlines. Officials are fairly certain they have the "main players" in custody, according to the Post.U.S. and British officials have subsequently raised threat levels to high alert, according to the Post. However, there is no indication of any plotting in the United States.The Post reports that passengers will have to undergo intense security checks and\u00a0considerable delays, and will be restricted from bringing carry-on luggage onto planes. The Transportation Security Administration announced that passengers on all U.S. flights, domestic and international, would be banned from transporting any type of liquid or gel in their carry-on luggage. The ban applies to all types of beverages, shampoo, toothpaste, hair gels and other items of a similar consistency.Authorities believe that terrorists were planning to smuggle liquids on board, which, when mixed in flight, make a volatile explosive.\u00a0Using timers and detonators, the terrorists would then detonate the explosives.Only mothers would be allowed to transport milk and baby formula on flights, but they would be required to have the liquids inspected in the United States\u00a0and taste the liquids in the presence of security guards before boarding in Britain, the Post reports.The article states that officials at Heathrow Airport, one of the busiest in the world, appeared on television and asked people not to travel to the airport at all if possible.British Home Secretary John Reid said the conspirators planned "a wave of attacks" on aircraft in flight. "Had this plot been carried out, the loss of life to innocent civilians would have been on an unprecedented scale," he said in a statement.Compiled by Paul KersteinKeep checking in at our Security Feed for updated news coverage.