Thousands of protesters have marched on Thailand's partly-privatised state oil company PTT, calling for it to be brought back into complete public ownership.

A third of the company was sold off under the government of ousted prime minister Thaksin Shinawatra.

The protesters, led by the anti-government People's Alliance for Democracy, blocked the main gates outside PTT headquarters in Bangkok.

The protest leaders say Mr Thaksin and his allies were the main beneficiaries of the public listing.

They also argue the dilution of state control has meant consumers have had to pay higher fuel prices.

Hundreds of police were on hand to prevent any repeat of the recent clashes that have occurred between pro- and anti- government groups elsewhere in the country.

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