• Plane went down over the Sinai on October 31 in disaster killing 224 people
• Forensic tests have now revealed bomb was stuffed under seat 30A or 31A
• Maria Ivleva, 15, was in 31A and travelling back from holiday with mother
• Nadezhda Bashakova, 77, was in 30A, and it's thought both died instantly
The bomb that blew up a Russian airliner over the Sinai desert last month was probably hidden under the seat of a 15-year-old girl, investigators believe.
Holidaymaker Maria Ivleva would have been killed instantly by the huge explosion just centimetres beneath her.
Reports in Russia say the device - which killed 224 people on October 31 - was likely to have been planted under seat 31A, where Miss Ivleva was sitting.
The teenager from St Petersburg had been on holiday in Sharm El Sheikh with her 44-year-old mother Marina, who was sitting in seat 31B.