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Online messages call for more protests on Wednesday

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600 prison places secured amid overcrowding crisis

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About 400 people have been arrested so far

By Sachin Ravikumar and Kate Holton

LIVERPOOL, England, Aug 6 (Reuters) - The British

government has increased its prison capacity to help tackle

violent, week-long anti-immigrant riots that have prompted a

growing number of countries to warn their citizens about the

dangers of travelling in Britain.

Riots across a number of towns and cities have erupted

following the murder of three girls at a Taylor Swift-themed

event in Southport, a seaside town in northern England, after

false messaging on social media wrongly identified the suspected

killer as an Islamist migrant.

The Justice department, which is being forced to release

some prisoners early as it battles a jail overcrowding crisis,

said nearly 600 prison places had been secured to accommodate

those engaged in violence.

About 400 people have been arrested so far.

"My message to anyone who chooses to take part in this

violence and thuggery is simple: the police, courts and prisons

stand ready and you will face the consequences of your appalling

acts," Justice Secretary Shabana Mahmood said.

The unrest has prompted India, Australia, Nigeria and other

countries to warn their citizens to stay vigilant.

Riva Peacock, a 22-year-old retail worker in Liverpool,

where rioters clashed with police over the weekend, said the

violence was shocking.

"There are a lot of people that blame immigrants for the

state of this country," she told Reuters. "It's just a real

shame that some of the most vulnerable people in our society

have been used as a scapegoat for these issues."

Prime Minister Keir Starmer has vowed a reckoning to those

who have attacked Mosques and hotels holding migrants, hurled

bricks at the police and counter protesters, and looted shops

and burnt cars.

Police on Tuesday charged a 28-year-old man with stirring up

racial hatred over Facebook posts linked to the disorder. A

14-year-old pleaded guilty to violent disorder.

On Monday night trouble flared in Plymouth, southern

England, and again in Belfast in Northern Ireland, where

hundreds of rioters threw petrol bombs and heavy masonry at

officers, and set a police Land Rover on fire.

A message online says immigration centres and law firms

aiding migrants would be targeted on Wednesday.

WIDESPREAD VIOLENCE

In the first widespread outbreak of violence in Britain for

13 years, hundreds of men, some women and children have attacked

hotels housing asylum-seekers from Africa and the Middle East,

chanting "get them out" and "stop the boats," in reference to

asylum seekers arriving in southern England on small dinghies.

They have also pelted mosques with rocks, unverified videos

online have shown some ethnic minorities being beaten up and one

man photographed at a protest in Sunderland on Friday had a

swastika tattooed on his back.

In Birmingham, Britain's second largest city, videos online

on Monday evening showed a group of Asian men gathering with

Palestinian flags after reports that anti-migrant protesters may

target the area.

Reporters on the scene said they were met with hostility and

videos appeared to show one white man being attacked in a pub.

The prospect of clashes between white and ethnic minority

groups revived memories of race riots that broke out in Oldham

and other northern English towns in 2001 - which an official

report later attributed to a lack of social cohesion, with two

communities living parallel lives.

The government has said riots in recent days were not a

proportionate response to concerns about immigration, but

violence whipped up by far-right agitators and supported by

football hooligans and young people.

(Writing by Kate Holton in London; Editing by Conor Humphries)