It was 7am when Somchai Jaideechei and his family accepted that the end was near for their 28,000 chickens. That was when a government-contracted excavator arrived on their farm in Phai Khad village and began digging a massive burial pit.

The farmers knew what was to follow because they had witnessed their neighbour's birds being destroyed the day before. All that remained was a circle of white lime where chemicals had been mixed with the still-clucking poultry as they had been buried alive. Twenty metres away stood the empty chicken sheds.

'There's nothing we can do so we just want to get it over with now,' Somchai said. 'We've been through so much we just want to put it behind us.'

For Somchai and the tens of thousands of poultry farmers in Suphanburi province, 70 miles north of Bangkok, 'so much' has been weeks of lies and uncertainty as they watched their stock fall ill for no apparent reason.

It was only on Friday that the government finally admitted what the farmers had privately guessed from the outset last November: their birds were infected with avian flu, a killer illness which has ravaged much of East Asia and has started spreading to humans.

'They kept telling us it was bird cholera and bronchitis,' said Somchia's elder sister, Yupa Jaideechei, whose own poultry were next in line for destruction. 'But we found that hard to believe because our birds continued to fall ill even after we had vaccinated them against cholera and bronchitis.'

Two young Thai boys, one from Suphanburi province, are critical in hospital with bird flu and several other people are suspected to have it. In Vietnam, where the bug first appeared, a sixth human death was reported yesterday.

Japan and the European Union, Thailand's two largest export markets, have banned Thai poultry products, as have several other regional countries. The crisis is expected to cost Thailand several billion pounds - if it can be resolved in the 30 days the government is promising.

Doubt remain as to whether it can: events at Somchai's farm demonstrated how haphazardly, and almost arrogantly, the Thais are handling the crisis.

With the slaughterers due at any time, a couple of Somchai's farm workers hurriedly dragged a cart laden with black buckets to collect the thousands of eggs laid overnight. It turned out they need not have rushed because the 'team', as the bird cullers are euphemistically dubbed, arrived two-and-a-half hours late.

To describe them as rag-tag would be a flattering complement. While the government had promised to deploy hundreds of soldiers and officials to conduct the slaughter, this 'team' was a motley crew of local villagers. Dressed in grubby farm clothes, the only protective gear they had were masks. Most wore flipflops and only a lucky few appeared to have gloves, woolly ones with holes rather than the more suitable rubber variety.

Despite Somchai wishing the slaughter completed as quickly as possible and the 'team' wanting to get on with it, the culling could not begin because no one from the agriculture ministry was present to complete the necessary paperwork.

Several frantic phone calls located the missing official, but he said he would not be available for at least another hour. Another two-and-a-half hours later, more than 10 hours after the excavator arrived, the slaughter began. Ten birds were stuffed into each sack, which was tied up, thrown into the pit and covered in lime and disinfectant.

An estimated eight million birds have died or been culled across Thailand, but it is impossible to get an accurate picture of the scale of the crisis because the officials are scrambling around with very incomplete data.

The deputy agriculture minister, Newin Chidchob, who went to Suphanburi to co-ordinate the operation, said that only 113 poultry farms in Suphanburi were registered a week ago with the livestock department as having been infected. 'But it turns out there are 530,' he said. 'We have cleaned 330 and have 200 more to do. We should complete the job in two to three days.'

Newin seemed to be saying what he believed to be true, but it is unlikely that he has the full facts because the officials overseeing the slaughter are so afraid of their bosses they are withholding information. 'Look, I can't really talk to you,' said the livestock department official co-ordinating the slaughter at a farm five miles from Somchai's. 'I don't want to get into trouble.'

The prime minister, Thaksin Shinawatra, insisted in his weekly radio address that there had been no cover up. 'If we came out and said this was it [bird flu] without the lab results, it would have caused even more panic,' he said.

Newin said the government would fully compensate the farmers. 'We will pay for the actual birds destroyed, we will give compensation for loss of income for the period they cannot earn and we will defer their loan payments,' he promised.

Compared to many of his neighbours Somchai is lucky because he has a timber business to fall back on. But that won't make up for what he's endured for the past three months.

'It seems the government just wanted to please the exporters,' he said. 'No one was looking out for us, the small farmers.'