Malaysia Airlines Flight 17 crashed in eastern Ukraine, Thursday, July 17, 2014, en route from Amsterdam to Kuala Lumpur. The plane, which was carrying 295 people, was shot down.

Two more top leaders from the armed insurrection in eastern Ukraine resigned Thursday as government forces closed in on the last two strongholds of the four-month-old uprising.

Igor Girkin, who reportedly bragged of shooting down a Ukrainian jet on the day that a Malaysia Airlines passenger plane was blown from the sky, and self-proclaimed Luhansk People's Republic Gov. Valery Bolotov, were both reported by Russian media to have resigned.

Bolotov's departure was reported by Russia's Itar-Tass news agency to be "temporary" while he recovers from an unspecified injury. Bolotov has been the political frontman for the breakaway Luhansk region since voters in the Russian-speaking community chose to declare independence from Kiev in May.

Girkin, better known by his nom de guerre Strelkov, or Shooter, was said by the separatists' New Russia online news agency to be leaving for another, unspecified position. A Russian citizen and special forces veteran, Girkin will be replaced as commander of the flagging insurgency by a local deputy, Vladimir Kononov, the news agency said.

Ukrainian security officials claimed after the July 17 downing of Malaysia Airlines Flight 17, in which all 298 on board were killed, that it had intercepted a radio announcement by Girkin that his forces had just shot down a Ukrainian military transport. The presumably mistaken destruction of the passenger jet sparked international outrage and cast Russian President Vladimir Putin as responsible for the tragedy because of his support for separatists.

The resignations of Bolotov and Girkin follow by less than a week word that Oleksandr Boroday, the scruffy, fatigues-clad separatist leader in Donetsk, was returning to his native Russia and leaving the insurgency in the hands of a local militant.

News of the departures coincided with the insurgents' loss of another key town to Ukrainian government forces who have encircled Donetsk and Luhansk. Military leaders in Kiev this week claimed to be in the "final stages" of routing the insurgency that was sparked by Russia's March annexation of Ukraine's Crimea territory.

Putin, who is accused by the Ukrainian government and Western allies of fomenting the bloody uprising, was in the Crimean resort town of Yalta on Thursday to address lawmakers and pledge more than $19 billion in investments to improve infrastructure on the annexed peninsula.

Crimea used to get most of its food and energy from mainland Ukraine -- vital supplies disrupted by the Russian annexation. The annexation has also isolated Moscow in the international community.

Putin vowed to bring an end to the bloodshed in Ukraine, which has claimed more than 2,000 lives over the last four months, the United Nations human rights agency reported this week.

But the Kremlin leader continued to cast the deadly fighting as a campaign of aggression against the Russian minority in Ukraine since a pro-Europe rebellion ousted Ukrainian President Viktor Yanukovich, a pliable Kremlin ally.

Putin dispatched what he called a humanitarian convoy of 280 trucks to eastern Ukraine this week but has declined to submit to the conditions set by Kiev that the aid first be inspected by Ukrainian customs officials, then handed over to the International Committee of the Red Cross for transport to civilians trapped in embattled Luhansk.

The standoff over the Russian aid mission has sharpened tensions in the area, as Kiev officials say they fear the convoy is a pretext for a Russian invasion or resupply of the embattled separatists.