Over 100 protesters Friday denounced the military overthrow of Prime Minister Thaksin Shinawatra as undemocratic, in the first anti-coup rally since the premier was deposed three days ago.

"Don't call this reform, this is a coup!" said one sign held by protesters who stood scattered in several groups to avoid new military restrictions banning public gatherings of over five people. At one point, protesters staged a sit-in in groups of under five people.

The protest was held outside Bangkok's poshest shopping mall, Siam Paragon, which closed temporarily during the one-hour gathering.

The protesters broke up afterward, and there was no apparent police or military presence. Protest organizers said that seven people were detained but Bangkok police spokesman Pinit Maneerat said no protesters were arrested.

CountryWatch: Thailand

Meanwhile, Thailand's new military rulers appointed nine people Friday to investigate corruption under Thaksin's rule and announced plans to write a new constitution to hold future leaders more accountable.

Under sharp criticism from the international community for their coup, the military rulers were moving to appoint a civilian interim prime minister. A spokesman, Lt. Gen. Palanggoon Klaharn, said that would take place within two weeks, as promised.

The military leaders reaffirmed their "intention to bring back peace and order," said Lt. Gen. Palanggoon Klaharn, a spokesman.

He also sought to quash rumors circulating in Bangkok of a possible countercoup.

"Soldiers must strictly adhere to the orders of their commanders. The rumor about a countercoup is untrue," Palanggoon said.

Since the Tuesday night takeover, the coup leaders have announced a series of measures to tighten controls until an interim government is installed. Aside from banning public gatherings, there have been restrictions placed on the media.

One protester, a 27-year-old student Chutimas Suksai, said she was opposed to the limits on media. She said she had been trying unsuccessfully to access foreign news Web sites.

"I think even when you have a coup you should have freedom of expression," she said.

Krich Aremcharoen, 33, another student, said he anticipated more protests.

"I think we are the first wave. We are the first people to say we love democracy," he said. "I don't care if I'm arrested. We need people dedicated to what we believe."

FOXNews.com Reporter's Notebook: Thai Crisis