* Russians used stun grenades, fired automatic weapons
* Base one of last remaining symbols of resistance
* Ukraine stand-off worst East-West crisis since Cold War (Adds officers taken away)
By Aleksandar Vasovic
FEODOSIA, Ukraine, March 24 (Reuters) - Russian troops used stun grenades to force their way into a Ukrainian marine base in Crimea early on Monday, overrunning one of the last symbols of resistance left after Moscow wrestled the peninsula away from Kiev, Ukrainian officials said.
The Russians fired weapons as they charged into the compound in the port city of Feodosia, and Ukrainian officers were taken away for questioning, a soldier inside and a Ukrainian military official told Reuters.
Ukrainian flags were taken down inside the base two days after Russian forces used similar tactics to take a Ukraine's Belbek airbase in Crimea.
Russia's seizure of Crimea after the ousting of Ukraine's pro-Russian president by mass protests in Kiev has triggered the worst East-West crisis since the Cold War.
The United States and the European Union have targeted some of Putin's closest long-time political and business allies with personal sanctions.
Russian forces had already captured part of the Feodosia base, used by the 1st Separate Marine Battalion, Ukraine's top military unit, earlier this month.
But Ukrainians had previously appeared to be in control of the armoury, the barracks and other facilities in the compound.
Ukrainian army officer, First Lieutenant Anatoly Mozgovoy, told Reuters by phone from inside the compound on Monday that the Russians had fired shots and the Ukrainian soldiers were unarmed. Asked if the base had been taken over, he said: "Yes".
"The invading troops were using stun grenades and also firing automatic weapons. The interior of the compound is full of Russian troops," said Vladislav Seleznyov, a Ukrainian military spokesman in Crimea.
Seleznyov said Russian forces were taking away all Ukrainian officers from the base to another location in the city for questioning.
Russian troops used armoured vehicles, automatic gunfire and stun grenades to take the Ukrainian Belbek airbase on Saturday. Ukrainian forces also abandoned a naval base after attacks by pro-Russian protesters, and had to surrender two flagship vessels to Russian forces over the recent days.
Moscow formally annexed Crimea on Mar. 21, five days after the region overwhelmingly voted in a referendum to join Russia, in a move not recognised by Kiev and the West. (Writing by Gabriela Baczynska; Editing by Andrew Heavens)