The captain of missing Malaysia Airlines flight MH370 received a two-minute call shortly before take-off from a mystery woman using a mobile phone number obtained under a false identity.
It was one of the last calls made to or from the mobile of Captain Zaharie Ahmad Shah in the hours before his Boeing 777 left Kuala Lumpur 16 days ago.
Investigators are treating it as potentially significant because anyone buying a pay-as-you-go SIM card in Malaysia has to fill out a form giving their identity card or passport number.
Introduced as an anti-terrorism measure following 9/11, this ensures that every number is registered to a traceable person.
But in this case police traced the number to a shop selling SIM cards in Kuala Lumpur.
They found that it had been bought ‘very recently’ by someone who gave a woman’s name – but was using a false identity.
The discovery raises fears of a possible link between Captain Zaharie, 53, and terror groups whose members routinely use untraceable SIM cards.
Everyone else who spoke to the pilot on his phone in the hours before the flight took off has already been interviewed.