Russia has released a video of a Ukrainian naval officer apparently “confessing” that he provoked the Russian navy into firing on his ship—but he appears to be reading from a prepared script. A man billed as a Ukrainian naval captain says he “ignored requests to stop on purpose” and that the presence of the ships was a “provocation.” Russia has warned about a flare-up in violence in eastern Ukraine after the Kiev government imposed martial law in response to Russia forces firing on and seizing three of its naval vessels. Russia-backed separatists in east Ukraine have been fighting Ukrainian troops since 2014, but the hostilities have largely eased since a 2015 truce. However, Dmitry Peskov, spokesman for Russian President Vladimir Putin, told reporters Tuesday that martial law might trigger an escalation in hostilities in the east. Meanwhile, Putin has told German Chancellor Angela Merkel that he is “seriously concerned” about the weekend’s escalation, but appeared to wash his hands of any responsibility. Putin said he hoped “Berlin could influence the Ukrainian authorities to dissuade them from further reckless acts,” according to a Kremlin statement. Six Ukrainians were reported to be injured in the Sunday clash, one of them critically.