A drone is said to have hit a plane that was about to land at Heathrow Airport, according to the Metropolitan Police.

The incident at the UK airport highlights the growing need for regulation over the operation of drones, as they could have a potential harmful impact if they are flown in restricted areas.

The British Airways flight, with 132 passengers and five crew members on board, were on a flight from Geneva when the plane was hit by a drone just prior before landeding at the London airport.

The pilot of the Airbus A320 reported that an object, believed to be a drone, had hit the front of the plane.

After receiving the report, aviation police based at the Heathrow airport have started probing the incident. However, the police, so far, have not detained anyone in connection with the incident.

A British Airways spokesman told the BBC:"Our aircraft landed safely, was fully examined by our engineers and it was cleared to operate its next flight."

The spokesman added that the airline will provide the police "every assistance with their investigation".

Terming it as "totally unacceptable" to fly drones near airports, a Civil Aviation Authority (CAA) spokesman said that violation of rules may invite "severe penalties, including imprisonment".

Calling for a "greater enforcement" of the current rules, Steve Landells, from the British Airline Pilots Association (Balpa) said it had been "only a matter of time before we had a drone strike".

Under the existing rules, flying a drone close to an airport is punishable with imprisonment of up to five years. The rules also do not allow flying drones above 400ft (122m) or near buildings and crowds of people.

However, the latest drone incident will likely put further pressure on policymakers to initiate more measures to prevent such incidents. James Stamp, global head of aviation, at KPMG said:

"People who fly drones in controlled airspace are potentially putting lives in danger, and should be subject to the strongest possible sanctions available under the law. A number of practical steps should be taken, including requiring drones to be registered, tougher penalties for irresponsible behaviour, and technology based solutions that will prevent the drones entering restricted airspace in the first place.

"More research is also required into the potential impact of collisions because, while the impact of bird-strikes has been well researched, the impact of drone impacts is less well understood."

In February this year, Airline pilots had called for urgent action on drones after four separate near miss incidents at UK airports.

The UK Airprox Board (UKAB) had provided details of a series of incidents involving drones, of which four were considered to be the most serious cases belonging to category A where a severe risk of collision happens.

In one incident, a drone almost collided with a Boeing 737 taking off from Stansted Airport. The category A incidents also took place at Heathrow, London City and Manchester airports.

Recently, the US government launched a compulsory registration scheme for drones in order to identify the owner in case of accidents.

In a bid to avoid flying drones in restricted areas, US officials may make it compulsory for owners to run geo-fencing software in drones.

The US department for transport has promised a "strategy for unmanned aircraft" later this year. Pilots have asked the DoT to fund projects that assess the consequences of a drone hitting an aircraft engine or plane’s windscreen.

While a considerable amount of research has been done in identifying the dangers from bird strikes, there is little information on the impact of drone strikes on a plane, the British Airline Pilots Association noted last month.

Earlier this year, the head of the International Air Transport Association (IATA) had cautioned that drones operated by the general public pose "a real and growing threat" to civilian aircraft.

Tony Tyler, director and CEO of IATA, said that drone regulations need to be rolled out before an incident causing severe damage happens.

According to the UK Air Proximity Board said there were many cases of "serious near-misses at UK airports involving drones."