Russia has been sending weapons to rebels in areas of Ukraine controlled by pro-Russian separatists, according to Associated Press reporters who have viewed the convoys. The development seems to discount Moscow’s insistence that the trucks are sending only humanitarian aid to eastern Ukraine.

In the eastern Ukrainian town of Krasnodon, AP reporters saw three convoys filled with military weapons and supplies from vehicles coming from Russia. Pro-Russian separatists told the news wire service that the convoys weren’t being stopped by Russian border guards.

Moscow has denied claims by NATO that it is sending weapons to rebels in eastern Ukraine. The Ukrainian military said it clashed with rebels that had armored vehicles that were sent by Russia, the BBC reported Monday. It said two tanks were destroyed and a column of 10 tanks and armored personnel carriers were stopped near Mariupol in southeastern Ukraine.

News of the convoys came days after the White House accused Russia of painting military vehicles to look like civilian trucks. Washington called the move a “direct invasion.”

"Russia’s decision … to send in its vehicles and personnel without the [International Committee of the Red Cross] and without the express permission of the Ukrainian authorities only amplifies international concerns about Russia’s true intentions," said National Security Council spokeswoman Caitlin Hayden, according to Business insider. "It is important to remember that Russia is purporting to alleviate a humanitarian situation which Russia itself created — a situation that has caused the deaths of thousands, including 300 innocent passengers of flight MH17. If Russia really wants to ease the humanitarian situation in eastern Ukraine, it could do so today by halting its supply of weapons, equipment, and fighters to its proxies. This is a flagrant violation of Ukraine’s sovereignty and territorial integrity by Russia. Russia must remove its vehicles and its personnel from the territory of Ukraine immediately."

Meanwhile, Ukrainian President Petro Poroshenko dissolved parliament amid the crisis. He said in a televised address that elections would begin Oct. 26, according to the BBC.

The crisis in Ukraine between pro-Russian separatists and the Ukrainian military has led to 2,000 deaths since June. The Donetsk and Luhansk regions, in the eastern portion of the country, declared independence from Ukraine after Russia annexed Crimea in March.