AFP - Red-clad Thai anti-government protesters promised entertainment for the crowds Thursday in a bid to boost dwindling numbers at their rally, vowing to step up demonstrations at the weekend.

The supporters of deposed premier Thaksin Shinawatra have so far failed in their drive to bring down the government, despite headline-grabbing symbolic blood protests and a 100,000-strong demonstration at its peak on Sunday. Related article: Thai protesters give blood

Police said 38,000 "Red Shirts" remained at their main rally site in Bangkok's government quarter late Wednesday as many returned to their homes in rural provinces, some having been in the capital for five days.

But the group's leaders remained defiant, announcing a day of meetings throughout Thursday to discuss tactics, followed by an evening of music and dancing -- apparently designed to keep spirits and numbers high.

"We will have cultural performances on this stage from each region, in order to strengthen relationships of our Red Shirt people," leader Nattawut Saikur told the crowds Wednesday evening.

He said the protest, which has been overseen by a massive contingent of security forces, would on Saturday "spread out on every road across Bangkok to appeal to more people to join us".

"We are ready to prolong our rally until we win," Nattawut added.

The Reds are campaigning to bring down the government of Prime Minister Abhisit Vejjajiva, which came to power via a December 2008 parliamentary vote after a controversial court ruling ousted Thaksin's allies. Related article: Key dates in Thaksin saga

The mainly poor and rural followers of Thaksin, a billionaire telecoms tycoon who lives abroad to avoid a jail term for corruption, fervently support the populist policies he introduced before his ouster in a 2006 coup.

Despite waning numbers, their rally paralysed streets on Wednesday as most of the group left their base for Abhisit's house, at which some threw bags of protesters' blood.

It was their third display of crimson anger since Tuesday, when they pressed their demand for Abhisit's resignation by collecting 300 litres (more than 600 US pints) of their own blood, some of which was poured at his office gates.

Government reaction to the bloody spectacles has been muted, but a minister attached to the prime minister's office on Wednesday said it was "uncivilised".

"Blood is a symbol of violence and hurling it at the house is saddening. The prime minister is speechless over this incident," Satit Wongnhongtaey told reporters.

On Wednesday Abhisit flew to Thailand's far south, where a six-year separatist insurgency is raging. Satit said intelligence reports had repeatedly warned of assassination attempts on Abhisit.

Some of the Reds delivered a letter to the British embassy in Bangkok Wednesday, saying they wanted to counter false British media reports about the protests.

Later a larger group peacefully picketed the US embassy, delivering a second letter of protest after unsubstantiated rumours that US intelligence officers had bugged a phone call of Thaksin and accused him of inciting violence. Related article: Thai protesters picket US embassy

Montenegrin police confirmed on Wednesday that Thaksin himself was in Montenegro, having travelled there on March 13 from Dubai.Related article: Thaksin in Montenegro