Police in Chile have been filmed firing pellets at protesters kneeling down with their hands up as the attempt to restore order after a week of demonstrations.

Video posted on Twitter shows officers driving armoured vehicles towards activists blocking a road in capital Santiago before opening fire in an attempt to clear them.

What began as demonstrations against increased transport fares has spiralled into a week-long outcry against social inequality, largely targeted at President Sebastian Pinera, a billionaire businessman.

Police in Chile have been filmed firing pellets at protesters kneeling down with their hands up

Sixteen people have been killed, hundreds wounded, and millions of dollars worth of damage caused so far.

The situation was not helped when Pinera's wife, Cecilia Morel Montes, was caught on tape describing the protests as an 'alien invasion'.

'We're going to have to cut back on our privileges and share with the rest of them,' she added in a message to a friend on WhatsApp that was subsequently leaked.

She has since apologised, saying: 'I felt overwhelmed by the circumstances... [it was] a personal state of mind made it seem like a general state of government.

'We are not for more divisions, but want to unite, listen, speak and seek solutions.

What began as demonstrations against increased transport fares has spiralled into a week-long outcry against social inequality

The situation was not helped when Pinera's wife, Cecilia Morel Montes, was caught on tape describing the protests as an 'alien invasion'

Video posted on Twitter shows officers driving armoured vehicles towards activists blocking a road in capital Santiago

'What we are experiencing runs very deep and all actors in society must work to reduce inequality, be more humble and improve opportunities for all.'

As she apologised, her husband was sending the first bill to congress to overturn a recent hike in electricity rates, saying he heard protesters' demands 'loud and clear'.

He said he would follow it on Friday with a bill to increase the minimum pension by 20 per cent.

'I will keep sending projects to Congress to ... breathe life into this social agenda,' Pinera said.

However that did not stop protesters coming out on to the streets Friday as truck and taxi drivers brought gridlock to the capital's in a protest against high road tolls.

Sixteen people have been killed, hundreds wounded, and millions of dollars worth of damage caused so far

On Friday morning, traffic was snarled along some major access points to Santiago as tractor trailer trucks, cars and taxis slowed to a crawl

On Friday morning, traffic was snarled along some major access points to Santiago as tractor trailer trucks, cars and taxis slowed to a crawl, honking horns, waving Chilean flags and bearing signs of protest at toll rates.

'No more tolls! Enough with the abuse!' read bright yellow-and-red signs plastered to the front of large trucks.

Chile's unrest is the latest in a flare-up of protests in South America and round the world - from Beirut to Barcelona - each with local triggers but also sharing underlying anger at social disparities and ruling elites.

Chileans on social media, meanwhile, were planning 'The Largest March in Chile' later on Friday, with rallies expected to paralyze major cities.

'These protests were necessary,' said street vendor Sergio Perez as he prepared a fruit stand. 'But they've made everything difficult, especially getting around.'

The streets of downtown Santiago were littered with trash and broken glass and reeked of tear gas early on Friday from the latest marches and clashes. Downtown traffic was light as many businesses and schools remained close.

Protester shows a sign that reads in Spanish 'Cecilia I come for you' in reference to First Lady Cecilia Morel's comments about the alien invasion

Riot police detain a demonstrator during the violent clashes in Santiago

Vandals set fire to underground transport trains and stops last weekend, sowing $300 million in damage and hobbling public transportation.

Chile's military has since taken over security in Santiago, a city of 6 million now under a state of emergency with night-time curfews.

'I used to take one bus to get to work, now I have to take four. This must stop,' said Julio Herrera, 71, as he waited at a bus stop on his morning commute.

President Sebastian Pinera, a billionaire businessman, told the nation on Thursday he had heard 'loud and clear' the demands of Chileans. He said he would send a bill to Congress on Friday to boost pensions by 20% for the elderly.

Chile's military has since taken over security in Santiago, a city of 6 million now under a state of emergency with night-time curfews

President Sebastian Pinera, a billionaire businessman, told the nation on Thursday he had heard 'loud and clear' the demands of Chileans

On Thursday, he sent lawmakers legislation to overturn a recent hike in electricity rates, among several measures he said he hopes will turn the protests into an 'opportunity'.

Prosecutors said on Thursday that since Wednesday night 734 more people had been charged in connection with protests, looting and arson nationwide, with 324 taken into custody in Santiago. More than 7,000 have been charged since Saturday.

An online poll conducted by local company Activa Research of 2,090 people between Oct. 22-23 found 83% of respondents said they supported the goals of the demonstrators, but 72.5% said they did not support violence as a method of protest.

U.N. human rights boss Michelle Bachelet, a former president of Chile, said she would send a mission to her homeland to investigate allegations of rights violations. The Chilean government said it would welcome a U.N. delegation, along with representatives of global NGO Human Rights Watch.

Foreign Minister Teodoro Ribera said there was 'no chance' the government would call off two major global meetings in Santiago in coming months, including welcoming U.S President Donald Trump and China's President Xi Jinping.