At least seven people are feared dead after two planes collided in mid-air over western Slovakia.
Local media reported that the aircraft were sports planes, but a fire service spokeswoman said it was not immediately clear how many people were on board.
The accident took place at around 8.30am GMT, near the village of Cerveny Kamen, around an hour from the capital Bratislava.
Travel expert Simon Calder says that changes to the rules on liquids in hand luggage are so minor that "you're much better off just thinking nothing's changed".
The Independent's travel editor told Daybreak that the changes risked creating "yet more confusion":
Gradual changes to restrictions on liquids in hand luggage are being brought in from today.
- Certain duty free liquids - those coming from outside the EU and being transferred in EU airports to a connecting flight - can be carried through provided they are sealed in the security bag when bought.
- If the sealed bag is tampered with, passengers will need to produce a receipt.
- In future, medicines in bottles larger than a 100mls will simply need to be presented for screening before being allowed on board.
- Australia, Canada and the US will also screen duty free liquids sealed in security bags by 31 January as well.
The 100ml limit on liquids in airport hand luggage will gradually begin to be lifted from today, it has emerged.
An EU ban on liquids in hand luggage was due to be lifted on 29 April last year, but was postponed by the European Commission.
However, duty-free bought liquids, such as aerosols, will now be allowed to go through airport security, so long as they are in a sealed bag.
Restrictions began in 2006 when a terror plot was uncovered to activate bombs disguised as drinks in hand luggage on at least seven flights from the UK to North America.
The EU plans to lift all restrictions by 2016.
Stansted Airport has said on Twitter that it is dealing with a power outage which is "impacting fight operations" at the London airport.
Delta Air Lines has confirmed that is has bought a 49% stake in Virgin Atlantic.
They will work together on more than 100 routes, it was announced.
Air passengers will today be given the first indication of how fares will change over the next five years at the capital's three main airports.
The Civil Aviation Authority (CAA) will outline its initial proposals for how much airlines will be charged for using London's three main airports between 2014 and 2019.
The plans will have an impact on fares at Heathrow, Gatwick and Stansted airports - the only three airports that are regulated by the CAA.
A final decision is due in January next year.
Passengers planning to fly to the east coast of the USA are being advised to check their flight status before leaving for the airport.
Snowstorm Nemo has led to a number of flight cancellations and delays.