Some amount of crystal meth and equipment used for taking the drugs are found in a police van, but police insist the drugs were planted. (Photo taken from Rangsiman Rome Facebook page)
Fifty-five people were treated for injuries and illness, including six for gunshot wounds, during clashes between rival demonstrators outside parliament on Tuesday.
Seven riot police also tested negative for drug use after some crystal methamphetamine was found in a police van.
Police claimed the drugs were planted in the vehicle, which had been surrounded and damaged during the confrontation.
The van's windshield was broken and some windows removed, and it was also sprayed with paint. Items that officers had left in the van were also missing.
Police were filing a complaint against people who distributed "fake news" regarding the drugs in the police van.
Photos of the drugs in the police vehicle were widely shared after an opposition MP posted them on social media on Tuesday.
Police insisted they had followed legal procedures in handing the protest. He said no rubber bullets or live ammunition had been prepared for the operation
Bangkok's Erawan Medical Centre said a total of 55 people were hurt, six of them for gunshot wounds and 32 for the effects of tear gas.
Four others fell ill and the 13 others had other injuries. They were treated at nine hospitals.
ammunition : bullets, bombs, etc that can be fired from a weapon - อาวุธยุทธภัณฑ์, ลูกกระสุน
crystal methamphetamine (noun): a white crystalline form of the drug methamphetamine that people take by inhaling through the nose, smoking it or injecting it with a needle -
fake : made to look like something real in order to trick people - ที่ทำปลอม
opposition : of a political party that is not part of the government or a group which is against the government - ฝ่ายค้าน ผู้ต่อต้าน
plant : to put something or someone in a position secretly - ฝัง
procedure : a way of doing something - ขั้นตอนการดำเนินการ
riot police : police who are trained to deal with violent groups of people - ตำรวจปราบจราจล
rubber (noun): a bouncy, elastic material used in car tires and waterproof gloves - กล้ายาง
tear gas : a gas used by some police and armed forces to control crowds of people. It hurts the eyes and makes them produce tears - ก๊าซน้ำตา
windshield : the large glass window at the front of a vehicle; a windscreen - กระจกหน้ารถ
wound : an injury in which your skin or flesh is damaged - บาดแผล