Three pro-Russian protesters are dead and thirteen are wounded after clashes broke out at a Ukrainian National Guard base on Wednesday.

The Ukraine Interior Ministry said around 300 protesters armed with grenades and firebombs tried to raid the base at the Black Sea port of Mariupol, according to Newsday. The violence is the worse so far to occur in the anti-Ukraine government uprising.

"They came here around 8:15 p.m., demanding that we surrender our weapons and join the people," Deputy Commander of the base Major Oleksandr Kolesnichenko told Reuters.

"Then they used a truck to break through the gate. There was some incoming fire. I could not see who was shooting- it was dark," the commander told Reuters. "We fired first into the air. We fired warning shots after they entered the compound. We had no casualties."

Authorities in the capital Kiev believe that Russian President Vladimir Putin, who annexed the Ukraine peninsula Crimea in March, is encouraging the violence as an excuse to send troops into the country.

Putin, who already sent Russian troops into Crimea earlier this year in defiance of the West, said the Ukraine government is to blame for the unrest. The president claimed the troops were necessary to protect the interest of ethnic Russians in the region.

"Instead of realizing that there is something wrong with the Ukrainian government and attempting to dialogue, they made more threats of force," Putin said during a four-hour televised event, according to Reuters. "This is another very grave crime by Kiev's current leaders.

"I hope that they are able to realize what a pit, what an abyss the current authorities are in and dragging the country into," Putin said.

However, Putin did admit for the first time that Russian troops played a role in Crimea by helping the local militia before the peninsula was annexed, Reuters reported.