LONDON: Two planes belonging to national carrier Pakistan International Airlines (PIA) were searched by British authorities as they landed in London on Monday.

Customs and immigration authorities searched the two PIA planes without disclosing details regarding the reason for the search.

Sources said passengers and flight crew were thoroughly searched along with luggage after flights PK 785 from Islamabad and PK 787 from Karachi landed in London. Aircraft equipment was also searched by custom authorities, with the raid lasting approximately one hour.

Sources added that the British authorities were in search of a specific person or item, but did not divulge details regarding the identity.

PIA spokesperson Rana Hanif told Dawn the spontaneous search of PIA passengers and aircraft by British authorities is 'routine'.

"These searches have become the norm. They check us whenever they want, even after the passengers have gone through their security checks. They offload passengers from the plane too. When they find nothing, they allow them to board and the plane to take off, " he said. He added that the last such incident occurred about a month ago.

"PIA has taken this up with British authorities through the Home Ministry," Hanif said, "Our country manager has also complained and a letter has been sent asking why these searches happen when the passengers have already gone through security checks at the airport.

He added: "As a nation we are humiliated, but we cannot put pressure on them.... look at the state of our country's security."

Take a look at: UK fighters divert PIA’s Manchester flight to London

Once a source of pride for the country, PIA's decay has made it the butt of jokes, one of which goes that its initials actually stand for 'Perhaps I'll Arrive'.

Flights are regularly cancelled and engineers say they have to cannibalise some planes to keep others flying.

Last year a PIA pilot was jailed in the United Kingdom for being three times over the alcohol limit before he was due to fly. Pakistani media reported that another pilot delayed a New York-bound flight for more than two hours as he waited for a sandwich delivery.

Read: Drunk Pakistan pilot arrested at British airport

Over the years, critics say, governments have manipulated state corporations like PIA for political and financial gain, giving jobs to so many supporters that the size of the workforce has become unsustainable in the face of mounting losses.

In September last year, customs authorities in Lahore detained most of the cabin crew members of a London-Lahore PIA flight, including its captain, for allegedly carrying unlawfully 24 iPhones worth about Rs2.5 million as well as foreign currency.

In another incident, a PIA airhostess was arrested in Italy after drugs were allegedly found on her at the Milan airport.