Germany's worst riots in decades at the weekend were condemned on Sunday as "deeply shocking" by chancellor Angela Merkel, who said she trusted the police would not allow further violence to disrupt this week's G8 summit.
The riots on Saturday in Rostock, north-eastern Germany, left almost a thousand people injured and overshadowed Germany's preparations for the summit.
The violence sparked new calls for extra security around the summit venue in Heiligendamm, a luxury resort 20km west of Rostock. Police on Sunday closed off roads near the resort and mounted spot checks on cars in the area.
German interior minister Wolfgang Schäuble said the police had acted correctly in trying to stop the "terrible violence". A police spokeswoman said: "We are prepared and will intervene accordingly if there is going to be further violence in the next days."
The violent street battles between militant activists and heavily-armed police on Saturday evening left approximately 430 police officers injured.
Mrs Merkel told German television that the riots "would not damage Germany's image abroad" as the "vast majority" of Germans were non-violent.
The clashes, in which protesters threw stones and set cars alight, and police retaliated with repeated baton charges, occurred after a largely peaceful march through Rostock by tens of thousands of anti-globalisation protesters.
Police used water cannon and tear gas to disperse the crowds, but also appeared to provoke the protesters by hitting protesters not directly involved in the violence.
Police and organisers on Sunday called for calm, but both expressed fears that the riots could reignite on Wednesday at the start of the G8 summit. 125 people were arrested on Saturday but less than 20 people remained in custody on Sunday evening.
Mr Schäuble defended the police action, but the parliamentary Left Party, a left-wing party, blamed recent police raids against anti-globalisation protesters had led to "an escalation in tensions" that had influenced Saturday's riots. Attac, the anti-globalisation group, said it was against potentially militant activists joining its anti-G8 protests this week.
A small anti-G8 rally with around 2000 protesters in Rostock on Sunday passed off without incident.
Organisers of Saturday's rally said on Sunday that around 520 protesters had been injured. Both the organisers and police blamed a hard-core of far-left activists - some from other European countries - for provoking the riots, which started when demonstrators attacked a police car parked near the Rostock portside rally ground where the street marches ended.
In several hours of chaotic scenes on Saturday evening, black smoke from burning cars hung over the city as protesters, many dressed in black and wearing face scarves to disguise their appearance, threw stones, bottles and sticks at police.
Organisers apologised to the police for the violence and distanced themselves from the estimated 2000 militant activists involved. However the organisers also criticised the police for using heavy-handed tactics, and for departing from their pledge ahead of the demonstration to remain in the background during the march and rally.
Many protesters from anti-poverty and environmental groups were shocked to see packs of police charge through crowds to pick out alleged troublemakers. Police were also seen kicking and hitting protesters with truncheons.
One young German protester who was holding a bandage to his forehead told the Financial Times he had been hit by a policeman as the security personnel charged through the crowd. A policeman standing in line confronting the protesters told the FT that several colleagues had been injured and it was necessary for the police to "defend themselves" by rounding up the troublemakers.
One elderly demonstrator watching the violence said the street battles were the "final spark" following weeks of tensions between the police and anti-G8 groups over security measures surrounding the summit. Campaign groups criticised police raids last month on dozens of anti-globalisation organisations.
Strains increased further last week when a court ruled that protesters were banned from going within five kilometres of Heiligendamm.
Campaign groups on Sunday expressed disappointment that the violence had overshadowed the rally, which they said had attracted 80,000. The police estimated the turnout at 25,000. Speakers at the rally called for swift movement on climate change, an increase in development aid and an abolition of the "elitist" G8 process.