Things started getting really tense at the Government House yesterday, as People's Alliance for Democracy (PAD) protesters took extra precautions against camouflaged enemies and prepared for a possible police attack.

The key PAD leaders, including Sondhi Limthongkul and Chamlong Srimuang, took turns in warning the crowds to be cautious, reminding them again and again that "we are at war".

On the third day of the siege, the Government House did look like a battlefield - PAD guards, wearing military-like outfits, were standing armed with clubs, batons and bamboo sticks. They built makeshift bunkers and barriers around the compound, and a bastion was built at entrance No 5 with bricks, tires and bamboo sticks.

"Please don't follow me [if they arrest me]. Stay here or we'll lose the battle," Chamlong advised the cheering crowd at 2am yesterday.

All the leaders urged the throng to remain seated and rally in an orderly fashion.

"Don't panic. If the police come, everyone must stay still," Chamlong told the crowds, as if commanding his troops on the battlefield. He was, after all, a military officer once.

He also gave the masses a do's and don'ts list, with practical, non-violent instructions to fight.

Both he and Sondhi emphasised the importance of capturing all the action on film. "Police may come and attack the ASTV [PAD's television station] cameramen first so it's important that you guys capture the images and we can tell the public about the violence," Sondhi said.

He also warned the protesters to be very cautious, alluding that there were around 100 plainclothes policemen in the crowd.

Quickly organised lessons in first aid were another sign that the leaders expected a flare-up.

In fact, the atmosphere was so tense last night that even innocent people were seen as the enemy. One elderly woman was dragged off for a grilling by the PAD guards just because she was seen being friendly with police officers. She says she was really disappointed because she was a true PAD supporter who had travelled to Bangkok from Ubon Ratchathani province.

Even female reporters had to suffer strong-arm tactics at the hands of PAD guards, who thought they might be "opponents" who had infiltrated the masses. "They [the opponents] come in disguises," the guards shouted at the reporters, as PAD supporters surrounded journalists from Matichon and Thai Rath newspapers.