
The student group called on the government to form a committee comprised of acceptable people to investigate the cause of the clash and explain it both in Thailand and abroad.
"During the investigation, the state must not take advantage of the committee's results to charge the demonstrators," the letter said.
The group urged the government to stop any action which threatened or deprived people of the right to express their political views, especially in public demonstrations.
The group also called on the government and the press to be careful in reporting such events to avoid any misunderstanding.
"We support all groups who intend to protect democracy in a peaceful way," the letter said.