Thousands of protesters took to the streets of Bangkok on Sunday, saying they won't go home until the prime minister resigns over allegations of corruption and abuse of power.

Police estimated Sunday's protest attracted about 15,000 people, but organizers said 60,000 people turned out to demand that Thaksin Shinawatra step down.

Led by a loose coalition called the People's Alliance for Democracy, the crowd included:

Protesters rally against Prime Minister Thaksin Shinawatra in Bangkok, Thailand on March 5. (AP Photo/Sakchai Lalit)

• Opposition politicians.
• Groups protesting everything from education policies to free-trade deals.
• Hundreds of monks from a banned Buddhist sect known as the "Dharma Army," whose leader spearheaded a successful populist revolt against a military-led government in 1992.

It was the latest in a series of protests against Thaksin in recent weeks, largely comprised of members from the country's middle class who were outraged after Thaksin's family sold his telecommunications empire in late January for a tax-free $1.9 billion US.

'We are here to rescue the country'

The protesters on Sunday rallied at a field in central Bangkok, then marched a kilometre to the Democracy Monument, which marks the end of the country's absolute monarchy.

"We are here to rescue the country and Thaksin has to get out," Sondhi Limthongkul, a media mogul who was one of the protest leaders, told the crowd.

"We have a consensus that we are to march our troops. ...We will move slowly and peacefully."

Some of the protesters – shouting "Thaksin Get Out!" and "Thaksin Resign!" – moved on toward the prime minister's office, but found hundreds of police blocking the road.

Thaksin refuses to bend to 'mob rule'

Thaksin has attempted to diffuse the mounting campaign against him by dissolving parliament in late February and calling a snap election for April 2.

The country's main opposition Democrat Party and two other parties are threatening to boycott the vote.

But Thaksin, who was campaigning in the rural northeast, told a rally on Sunday that the election would take place as planned.

"Every time there is a conflict like this, the prime minister always retreated," he told 20,000 supporters, according to the Associated Press. "But today, this prime minister will not give in because it will set a bad precedent by letting mob rule prevail."

Thaksin's supporters – who belong mainly to Thailand's rural masses – have also held rallies involving tens of thousands of people.

The most recent drew 150,000 supporters on Friday to the same square in central Bangkok where Thaksin's opponents gathered two days later.