The number of plane crash victims identified by Russian families has risen to 33 as rescue teams in Egypt combed the Sinai desert for more remains and parts of fuselage.
The Metrojet Airbus A321-200 carrying Russian holidaymakers from Sharm el-Sheikh in Egypt back to Russia's second-largest city of St Petersburg crashed over the Sinai Peninsula early on Saturday, killing all 224 people on board.
Only one body has been released for burial so far.
Relatives have identified 33 bodies and the paperwork is close to ready on 22 of those, meaning the families should get the bodies shortly, Igor Albin, deputy governor of St Petersburg, said.
Russians were still seen sobbing in grief on Wednesday at the unruly pile of flowers, photos and stuffed animals at the entrance to St Petersburg's Pulkovo Airport.
In the Sinai, Russian and Egyptian rescue workers were still scouring the desert after expanding their search area to 40 square kilometres. The plane's tail was reportedly found five kilometres away from the rest of the wreckage.
Russian officials say the plane broke up in the air 23 minutes following take-off after reaching an altitude of 31,000 feet. But they have refrained from announcing the cause of the crash, citing the ongoing investigation.
Metrojet, the plane's owner, and Russian authorities offered conflicting theories of what happened. Metrojet officials have insisted the crash was due to an "external impact", not a technical malfunction or pilot error. Russian officials have said it is too early to jump to that conclusion.
Two US officials said that US satellite imagery detected heat around the jet just before it went down. The infrared activity could mean many things, however, including a bomb blast or an engine on the plane exploding due to a malfunction.
One of the officials said a missile striking the Metrojet was ruled out, because neither a missile launch nor an engine burn had been detected.
Some aviation experts had earlier suggested a bomb was the most likely cause of Saturday's crash, while some others pointed to a 2001 incident in which the Metrojet plane damaged its tail during a rough landing.
Meanwhile Egypt's Islamic State (IS) affiliate has allegedly reiterated its claim to have downed the plane.
In an audio recording circulated among militant supporters online, a speaker said the crash coincided with the anniversary of the group's pledge of allegiance to IS.
The dates of the crash and the pledge roughly coincide according to the Islamic calendar.
Experts say the militants lack the sophisticated arms needed to shoot down a plane at cruising altitude. The speaker did not say how the militants brought down the jet.
The Associated Press could not independently verify the recording but it resembled previous statements issued by the group.
The US-based SITE Intelligence Group, which monitors jihadi websites, picked up the recording and circulated a translation.
Egyptian president Abdel-Fattah el-Sissi said an earlier IS claim was "propaganda" aimed at damaging Egypt's image.