Bangkok, Thailand (CNN) A manhunt is underway for a Thai soldier accused of killing at least 20 people in a shooting spree that began at a military site and then sent shoppers hunting for cover after the suspect entered a mall, authorities told CNN.

"We can't confirm if there are any hostages taken. But we believe he (the shooter) is still holding inside Terminal 21 shopping mall. We are working on this," Lt. Gen. Thanya Kiatsarn on Saturday told CNN from the scene.

"At the moment we are trying to capture the guy," police spokesman Col. Krissana Pattanacharoen said. "Both police and military forces have been deployed to the area."

Hours after the rampage began, heavily armed officers led some people out of the mall, images posted to social media showed.

Thai soldiers and paramedics gather outside the Terminal 21 shopping mall where dozens of terrified shoppers were evacuated amid a manhunt for a mass shooting suspect.

Police and someone believed to be the suspected gunman could be heard yelling at one another amid bursts of gunfire on video posted to social media. CNN could not independently confirm the authenticity of this video.

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