A senior police officer and a number have MPs have warned riots which swept England and led to nearly 3,000 arrests in the capital alone could flare up again.
Chairman of the Metropolitan Police Federation Peter Smyth told the Huffington Post UK that there would definitely be more "public disorder" and that August's riots could happen again.
"I think there will be more public disorder, because we know there are a number of events planned by certain unions. I think it's a fair guess that they'll turn into riots - there are a number of people off people out there who will use these events to agitate."
And he said riots like those in August could also happen again: "We saw what happened in August and we saw how quickly it mushroomed so we need to keep our eyes open. What would I imagine is that it would need a trigger - but if it broke out again then hopefully we'd be a bit more ready for it."
The police federation chair was responding to a ComRes poll of MPs which showed over half of MPs - 55% - believed there could be more disorder on the same scale. Smyth said the MPs were right to be concerned.
David Lammy, the MP for Tottenham - where the riots started - told HuffPost UK his constituents were also worried: "MPs concern that this will happen again is shared by the people in Tottenham, who have now seen two riots in a generation. The first riot was a tragedy and the second a disaster. A third would be catastrophic.
"After 1985 a community felt deserted when the television cameras moved out and the political spotlight shone elsewhere. That cannot be allowed to happen again. We cannot live in a society where the banks are 'too big to fail' but whole communities are allowed to sink without a trace."
The poll also showed Members of Parliament had lost trust in the police after the News of the World phonehacking scandal, with 58% agreeing that the Metropolitan Police were " insufficiently robust" when it came to combatting corruption.
And over a third of MPs said the riots had undermined their constituents' confidence in the police.
Peter Smyth at the Police Federation admitted that phone hacking had "inevitably" damaged the perception of the police, adding: "The conservative party still haven't forgiven us for arresting Damian Green."
However he said as yet no police officers had been convicted of corruption: "They said the News of the World had been paying police officers, but there's been nothing, months later. If there's evidence out there, let's see it."
ComRes chairman Andrew Hawkins said the findings showed MPs did not agree on the wider causes of the riots.
“MPs for the most part blame greed, opportunism and a lack of personal responsibility for the riots. However, there is no agreement on the wider underlying causes. MPs are able to identify the symptoms but there is no agreement over the root causes.”
The MPs polled said that greed, a lack of respect for authority, criminality and social breakdown were all to blame for the disorder - and 7% of Labour MPs blamed government spending cuts.
Most significant factors explaining why the riots occurred
· Greed & opportunism - 61% (71% Con, 54% Lab, 46% LD)
· Lack of sense of responsibility for own actions - 48% (52% Con, 42% Lab, 64% LD)
· Disregard for authority - 39% (49% Con, 29% Lab, 35% LD)
· Disregard for consequences of criminality of - 39% (38% Con, 38% Lab, 48% LD)
· Poor parenting - 27% (33% Con, 17% Lab, 27% LD)
· Long term breakdown in social institutions eg marriage - 15% (27% Con, 0% Lab, 8% LD)
· Lack of job opportunities - 11% (0% Con, 24% Lab, 14% LD)
· Anger at govt spending cuts - 3% (0% Con, 7% Lab, 0% LD)
However they were largely united on sentencing, with 75% overall saying riot punishments so far had been "proportionate". But over half of Liberal Democrat MPs agreed the riots sentences were "fairly disproportionate", highlighting a coalition split over sentencing.
So far nearly 1,774 people have been charged in connection with Augusts' riots.
ComRes surveyed a representative sample of 151 MPs on 1-23 September 2011.