Russia's Defence Ministry has said the wreckage of the military plane that crashed into the Black Sea on Christmas Day - killing all 92 people on board - shows no signs of damage from an explosion or fire, Russian media reported.
More than 3,000 people have been involved in the search for victims' bodies and aircraft debris. Two black boxes have since been recovered.
All possible causes of the Russian military plane disaster are being considered, including terror attack, the Russian transport minister has said.
Earlier, a Russian official had downplayed any suggestion of a terror attack.
But Maxim Sokolov said an "entire spectrum" of possible reasons is being considered.
However he added it's premature to speculate about the cause of Sunday's crash.
The Tu-154 plane belonging to the Defense Ministry crashed into the Black Sea two minutes after taking off from the Russian city of Sochi on Sunday morning.
The Democratic presidential candidate may also have shown his cards on his choice of running mate.
The US president also shared a post on Twitter accusing Dr Anthony Fauci of misleading the public over hydroxychloroquine.
Fears over an impending second wave of coronavirus dominates Wednesday’s front pages.