A large anti-corruption rally in Bangkok Friday night suggests that public sentiment against corruption in government is growing. The rally is part of a campaign being led by a former supporter of Prime Minister Thaksin Shinawatra.

Thai media executive Sondhi has set out to expose what he calls corruption and nepotism in the government of Prime Minister Thaksin Shinawatra. The campaign is apparently capturing the public's imagination.

Friday evening, Mr. Sondhi drew a crowd estimated by the police at more than 40,000 to an anti-corruption rally in Bangkok's Lumpini Park. That was far fewer than the half million people Mr. Sondhi had said he was hoping for, but still twice as many as showed up for a similar rally two weeks ago.

At Friday's rally, Mr. Sondhi accused the prime minister and his government of a broad range of misdeeds, from the alleged use of a military aircraft by Mr. Thaksin's sister to take friends to a party, to his son's involvement in companies that benefited from government contracts, to questionable spending on new electricity-generating plants.

He asks why the national electric company has to spend the equivalent of $485 million to generate less electricity than it did with less money before.

The rally comes two days after the prime minister, under pressure from Thailand's highly respected king, ordered his lawyers to withdraw several libel suits against Mr. Sondhi.

Those libel suits and several more filed against other critics of Mr. Thaksin are widely seen as an attempt by the prime minister to silence his opposition.

Mr. Sondhi began holding his rallies after his popular talk show on Thai state run television was cancelled last August. He had been using the show to criticize the performance of Mr. Thaksin's government, which won a large majority in parliamentary elections early this year.

Mr. Sondhi says he is not targeting Mr. Thaksin personally. He says he is only fighting for a transparent government, freedom of the press and political reform. He says people inside the Thaksin government have been supporting him with information.

His business offices have been attacked since he began the campaign, with thugs daubing pig manure on the building's walls. A small bomb also was set off near the building. It caused little damage, but was widely seen as a warning to Mr. Sondhi to back off.

Mr. Sondhi was close to Mr. Thaksin in the 1990's as they both built successful media empires. But Mr. Sondhi suffered major setbacks when Asia's financial crisis hit in 1997, leaving him $500 million in debt.

Banks came to his assistance, allowing him to make a comeback, and he was still a strong supporter of Mr. Thaksin during the prime minister's election in 2001. He began turning against Mr. Thaksin earlier this year.