The US believes that Islamist terrorists are developing bombs that could evade existing airport security checks.
While there is not thought to be any specific threat the fear is that Jihadis with Western passports and who have been trained by al-Qaeda, could enter airports armed with bombs that are almost invisible to air travel security measures.
ITV News Diplomatic Correspondent John Ray reports on the new security steps being put in place today:
More top news
Protestors angry about an immigration raid at Byron burger earlier this week reacted by launching hundreds of insects into the restaurant
Families and rebel fighters are believed to be among the people to have left besieged Aleppo on Saturday through safe corridors.
The balloon came down near Lockhart, Texas, around 8.30am local time.