Police and troops have poured into Peru's second city, Arequipa, to enforce a government-imposed state of emergency as violent demonstrations against privatisation spread.

Rioting which erupted on Thursday prompted President Alejandro Toledo to declare the emergency and authorise the military to use force to maintain order in the city.

One man has been killed and dozens injured in the unrest in Arequipa, 750 km (470 miles) south-east of Lima, which was sparked by the privatisation of two state electricity companies.

Hours after Mr Toledo said he would not go back on his privatisation plans, protesters rioted in Tacna, near the border with Chile, while demonstrators took to the streets again in Arequipa.

Hundreds of vandals wrecked phone booths and smashed windows of banks and official buildings in Tacna, briefly forcing the closure of the airport, local officials said.

Police responded with tear gas and made 30 arrests, with two of their own officers injured.

The central government representative in Tacna, Wilson Mazuelos, called for the state of emergency to be extended to include his city.

In Arequipa, 10 people were reportedly injured on Monday morning as protesters gathered in clusters in the centre but soldiers could be seen patrolling the streets.

Crackdown

President Toledo insisted in a televised address on Sunday that privatisation met the needs of people in Arequipa and urged citizens to show "serenity, calm and responsibility" after the clashes, estimated to have caused damage costing $100m.

A man struck by a tear-gas canister has died of his injuries while the Red Cross reports that 66 people, including 24 police officers, have been injured since Thursday.

Arequipa

Peru's second city, population 1 m Important tourist destination, close to the El Misti volcano Celebrated for its colonial architecture

Peruvian Interior Minister Fernando Rospigliosi said on Monday that the situation was "returning to normal".

He blamed the unrest on "irresponsible violent individuals".

According to the Reuters news agency, 700 soldiers armed with automatic rifles moved into the city early on Monday morning, backed by light armoured vehicles.

They were accompanied by an extra 1,000 police equipped with riots helmets and shields.

The troops moved to dismantle stone barricades erected by protesters who had crammed into the city's main square in their thousands over the weekend, for demonstrations which the police broke up with tear gas.

Protesters had also vandalised the airport, smashing landing lights and stealing equipment.

All flights were cancelled and many tourists were left stranded, but the airport was expected to reopen on Monday.

Funds pledge

The demonstrators have been protesting against the government's decision on Friday to sell off the state-owned utility companies Egasa and Egesur.

They accuse Mr Toledo of reneging on a pledge not to sell them, made during last year's election campaign.

Police are backed by heavily armed troops

Local residents fear they will see nothing of the $167.4m paid by the Belgian company Tractebel for the two companies.

But Mr Toledo counters that the sale has $85m for infrastructure projects, and says that Tractebel committed to making new investment of $90 million in the Arequipa region.

As a result, 60,000 people would receive electricity and 5,000 new jobs would be created in Arequipa, he said.

Privatisation - a key part of the government's economic policy - is an issue that has come to haunt the already unpopular president, whose current poll rating is about 20%.