The packages prompted a brief security scare but were quickly deemed harmless.

“There were two boxes that contain no material that could cause explosion. There are ball bearings and wire circuits, which is likely to cause alarm,” police deputy spokesman Krisana Pattanacharoen told Reuters.

He said security around the Asean forum had been tightened but it was unclear whether the meeting was the apparent hoax’s target.

China’s top diplomat Wang Yi and US secretary of state Mike Pompeo are attending the forum along with other regional and global officials.

Police major general Tawatchai Mekprasertkul told Reuters the packages were placed across the street from the forum venue, near a police station where Thai prime minister Prayuth Chan-ocha was due to visit on Friday.

Krisana said security cameras had shown a man wearing a yellow shirt placing the packages and police were trying to identify the suspect.