More than 30,000 people have protested in Bangkok in the campaign to force Thai PM Thaksin Shinawatra to resign.
The protesters are targeting key shopping areas in Bangkok
The three-day protest in the capital's shopping district which has disrupted business and traffic is the last rally before Sunday's general election.
Some opinion polls suggest support for the anti-Thaksin campaign is weakening and that residents are tiring of the disruption the rallies have caused.
Mr Thaksin's critics accuse him of corruption and abuse of power.
There have been weeks of protests by demonstrators calling for his resignation.
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On Wednesday, demonstrators descended on the glitzy new Siam Paragon shopping mall and camped out on the streets.
Organisers from the People's Alliance for Democracy (PAD) said protesters would stay at least two nights.
The mall, on one of Bangkok's busiest intersections, was closed in anticipation of the protest.
Traffic was gridlocked around the area and public transport was forced to cope with extra passengers.
Protesters draped banners reading "Get out Thaksin!" and "Thak, your time is up" and listened to speeches made from makeshift stages.
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Protest organisers were unrepentant about the traffic chaos the rallies caused.
Thaksin's offer to include opposition parties has been rejected
"Allowing this prime minister to continue in power is more dangerous to the country and more distressing to the public than a traffic jam," said Pipop Thongchai, a PAD leader.
But there were some indications the strategy might be counter-productive.
One opinion poll conducted by Assumption University on Monday showed 26% of Bangkok people supported the resignation of Mr Thaksin, compared to 48% three weeks previously.
Protest organisers say targeting the malls serves to highlight their belief that business will suffer if Mr Thaksin stays.
But the government says the protest could cost businesses 300m baht ($8m) a day.
Local travel agent Witoon Thanawanchai said: "They should not come and protest here. It has caused us a lot of trouble."
Mr Thaksin himself condemned the rally in the busy district, saying protesters were courting police action.
He has cancelled his own rally in a nearby park on Friday to "avoid confrontation".
His Thai Rak Thai party is expected to maintain its huge majority in the election on Sunday, but a boycott by opposition parties could make the result constitutionally invalid.
Mr Thaksin, who was visiting supporters in Lamphun near Chiang Mai on Wednesday, denies any wrongdoing and says he will not resign.
The prime minister has offered to include opposition parties in a new government if he is re-elected, but they have refused to participate.