A second explosion went off at Sathorn pier in Bangkok on Tuesday afternoon, following Monday's pipe bomb that killed at least 20 people and wounded more than 100.

The Bangkok Post reported that the bomb was thrown at about 1:20 p.m. local time from the bridge. It bounced into the water and exploded there.

Nobody has been reported injured. The Bangkok Post cited Transport Minister Prajin Juntong saying the bomb has been classified as an improvised explosive device (IED), and is similar to the one thrown yesterday at the Erawan shrine.

#ThaiJunta broadcast: More than 10,000 troops and police being deployed to checkpoints and roadblocks. #BangkokBlast pic.twitter.com/YOjExtoix5 — Steve Herman (@W7VOA) August 18, 2015

On Tuesday, Police in Bangkok released CCTV images of a man wearing a yellow T-shirt and carrying a backpack that they say set off the explosion on Monday. Several photos of the man were released with police saying he's: "The yellow shirt guy is not just the suspect. He is the bomber".