PAD campaigners say the government is too closely tied to former PM Thaksin [AFP]

At least 11 people have been wounded in the Thai capital after violent street battles between pro and anti-government forces.

Police said that gunfire broke out on the road to Bangkok's old international airport on Tuesday where thousands of demonstrators had surrounded the temporary offices of the country's prime minister.

"Eleven people were taken to hospital and six have been admitted," the Reuters news agency reported an unnamed emergency services official as saying.

Protesters threatening to overthrow the elected administration also started fires and physically attacked government supporters with sticks and swords.

Piyapong Pholvanich, a police colonel, said he could confirm that "there were gunshots".

Television footage showed at least two security guards from the anti-government People's Alliance for Democracy (PAD) firing handguns at the government supporters.

'Coup d'etat'

Kudeb Saikrachang, a spokesperson for the ruling People's Power Party (PPP), said: "The protesters want violence so that they can claim that the government cannot control the situation and they want the military to interfere with politics.

"Actually they are calling for a coup d'etat."

He said that he expected the opposition to lose legitimacy through lack of support.

Earlier on Tuesday thousands of protesters surrounded Bangkok's old Don Muang airport from where Somchai Wongsawat, the prime minister, and his cabinet have run the country since protesters occupied Government House in August.

Protest leaders said their aim was to prevent the government from meeting.

"We'll protest until there is no cabinet meeting," said Somsak Kosaisuk, a protest leader. "We'll interrupt their every attempt to ruin the country further."

But a government spokesman told the AFP news agency the weekly cabinet meeting normally scheduled for Tuesday was not taking place as the prime minister had not yet returned from the Apec summit in Peru.

"The cabinet meeting was rescheduled on Wednesday afternoon after prime minister Somchai arrives from Lima. The government has not cancelled or postponed its meeting," Nattawut Saikuar said.

Six-month campaign

The protest came a day after PAD supporters surrounded the Thai parliament building, forcing MPs to postpone a joint session.

Tensions soared last week after a demonstrator was killed and several others injured in a grenade attack on a PAD protest camp in the ground of Government House.

The PAD – a loose alliance of royalists, academics and businessmen - accuses the government elected in December last year of being tainted by corruption and of being a puppet of Thaksin Shinawatra, the exiled former prime minister who was ousted from power in a 2006 coup.

PAD leaders have called the latest protests the "final battle" in their six-month campaign to unseat the PPP, which has close ties to Thaksin.

Unions had said they would call a nationwide strike on Tuesday if the government did not quit, but the threatened walkout did not materialise.

Norm Hermant, a journalist in Bangkok, told Al Jazeera: "The PAD protestors ... have not been able to create enough pressure to force the government to resign or force the army to step in. Meanwhile their numbers have been continually declining.

"So they have been trying to push for what they call this final showdown.

"But numbers yesterday showed that it wasn't a final showdown. They didn't get anyway near the one hundred thousand people they were promoting that they would get."

The ongoing political crisis has stymied government decision-making and undermined confidence in Thailand's export-driven economy, which has also been hit by the global financial crisis.

According to the latest government data the Thai economy will grow at 4.5 per cent this year, its slowest rate in seven years – due both to slumping investment and a slide in exports.