Two men arrested on a Pakistan International Airlines plane after fighter jets were scrambled to escort it to a London airport remained in custody Saturday for questioning by the police, AFP reports.
The men were detained on suspicion of endangering an aircraft after the plane, which was carrying 300 passengers from the Pakistani city of Lahore to Manchester in northwest England, was diverted to Stansted airport outside London.
Armed police officers boarded the Boeing 777 and arrested two male British nationals, aged 30 and 41.
The incident was not believed to be terror-related. An airline source told AFP the incident had stemmed from a family row on board.
"There was a family of eight to 10 people on the plane and they were quarrelling among each other," the PIA source said.
"When PIA staff approached them and asked them to calm down, they told them to go away otherwise they would blow up the plane.
"PIA staff became scared and they raised the alarm to avoid any untoward situation."
Police said they were alerted 10 minutes before the plane was due to land in Manchester at 1:30pm (1230 GMT) on Friday.
They were told a threat had been made to the safety of an aircraft.
Fighter jets were scrambled to escort flight PK709 into Stansted, London's third-biggest airport, where it touched down at 2:15pm (1315 GMT).
It halted in a designated safe location away from the terminal building.
The arrested men were taken to a police station "where they will remain in custody pending interview by detectives", the local Essex Police force said.
The remaining passengers disembarked under police escort and were taken to the terminal building for a debriefing.
"The plane will remain at its current location and will be subject to forensic examination by specialist officers," the police said.
"At this point in time no suspicious items have been recovered.
"This incident is being treated as a criminal offence."
A Ministry of Defence spokesman said that Typhoon fighter jets had been launched from a Royal Air Force base after the incident was signalled by the plane's crew.
"Typhoon aircraft from RAF Coningsby have been launched to investigate an incident involving an aircraft in UK airspace," the MoD spokesman said.
Typhoons can be scrambled if the pilot or crew of a passenger aircraft sends out a passenger signal, he added.
"The purpose of going up is to investigate what the situation is," he said.
"Often when a Quick Reaction Alert aircraft is launched the details are not known, but it is known that a signal has been sent."
Typhoons patrolled over London last year when the city hosted the 2012 Olympic Games.
By strange coincidence, the PIA plane diverted to Stansted was the very same plane on the very same route -- Lahore to Manchester -- that was diverted to Stansted in September 2011 due to a bomb scare.
Friday's incident came just hours after a British Airways plane was forced to make an emergency landing at London Heathrow Airport with smoke billowing from an engine.