Prime Minister David Cameron told his nation Thursday that the government was "acting decisively" to restore order after days of rioting shocked his country and the world.

He spoke to Parliament on Thursday, "We will not allow a culture of fear to exist on our streets," Cameron said. "We will not let a violent few beat us."

Even as Brittish lawmakers were called back from their summer vacations to address the problem, Police raided houses to round up more suspects from four days of rioting and looting in London and other English cities.

Cameron told parliament members that he would look to cities like Boston for inspiration, and mentioned former Los Angeles and New York Police Chief Bill Bratton as a person who could help offer advice.

He said the government, police and intelligence services were looking at whether there should be limits on the use of social media sites like Twitter and Facebook to spread disorder.

Authorities are considering "whether it would be right to stop people communicating via these websites and services when we know they are plotting violence, disorder and criminality," he said.

Meanwhile, for the first time in four nights the streets of London were mostly quiet on Wednesday.

One reason for change -- the presence of 16,000 police officers.

But violent mobs took their business elsewhere -- mainly in northern cities of the United Kingdom.

So far, 922 arrests have been made in the last few days across the country with 401 suspects charged.

Authorities say reinforced police forces will remain on the streets while they aggressively investigate criminal activity carried out by the mobs and individuals.