Russia says it has arrested eight people in connection with Saturday's dramatic explosion on the Kerch Strait bridge in Crimea.
The bridge links Russia to Crimea, illegally annexed by Moscow in 2014. The damage was seen as symbolic blow to President Putin, who opened the bridge in 2018.
We still don't know what caused the blast. Russia was quick to suggest it was a truck bomb, and named the owner and driver of the vehicle.
Now, its FSB security service says eight arrests have been made - five of those held were Russians, while the others were Ukrainian and Armenian.
Kyiv called Russia's investigation "nonsense". Days earlier, the head of President Zelensky's office suggested the explosion was the result of infighting between different parts of Russia's security establishment.
The BBC's Steve Rosenberg gets in Putin's head
He doesn't have a Kremlin crystal ball, he admits, but BBC Russia editor Steve Rosenberg has been trying to get inside the Russian president's head.
Fast-forward from a February invasion that was expected to last a few days, to now, and Vladimir Putin is under pressure.
Our editor asks how far the president is prepared to go, exploring questions of resources, territory and escalation with the West.
"Will he be thinking he got it all wrong, that his decision to invade was a fundamental error? Don't assume so."
Germany rejects President Putin's gas offer
President Putin has said the West is to blame for intensifying the global energy crisis.
But he also told the Moscow energy forum on Wednesday that gas taps can be still turned on for Russian supplies to the EU, via the Nord Stream 2 pipeline.
Despite Mr Putin's declaration, a resumption of gas supplies is unlikely.
Nord Stream 2 was halted because of the invasion, and Russia's gas delivery to Europe using Nord Stream 1 has been severely disrupted for months, with Russia blaming technical problems, and recent leaks.
In response, the EU has accused Russia of weaponising gas supplies against the West - a charge the Kremlin has repeatedly denied.
Germany swiftly rejected Putin's new offer to send gas via Nord Stream 2.
'I have spoken to Putin only once' - Musk denies Putin war talks
Elon Musk has denied reports that he discussed the war in Ukraine with President Putin, after political risk consultant Ian Bremmer alleged that the Tesla CEO directly told him about the conversation.
Replying to a tweet asking if the allegations were true, Mr Musk said he only spoke to Mr Putin once - 18 months ago.
On what was discussed at the time, he told his 107.7 million followers that "The subject matter was space."
Last week, Mr Musk held Twitter poll with suggestions on how to end Russia's invasion on Ukraine. Suggestions included a proposal to hold votes in parts of Ukraine occupied by Russia that the Kremlin says it has annexed.