Support for Germany's anti-migration AfD party soared to a one-year high of more than 15 percent in the wake of the Berlin truck attack.

With a general election expected next September, the right-wing populist Alternative for Germany recorded a 2.5-point boost to 15.5 percent compared to last week, according to the survey for the Bild newspaper by the Insa institute which will be released Saturday.

Chancellor Angela Merkel's Christian Democrats lost 1.5 points to hit 31.5 percent while the Social Democrats, junior partners in the ruling coalition, ceded one point to 20.5 percent.

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German populist party AfD supporters hold a placard reading 'Merkel must go' during a protest rally in front of the chancellory in Berlin in the wake of the terror attack

Demonstrators heap more pressure on the Chancellor with a protest two days after the attack

The poll was carried out between Wednesday and Friday among 2,083 eligible voters.

The prime suspect in the assault on the Berlin Christmas market which killed 12 people was a failed Tunisian asylum seeker.

The suspect, Anis Amri, who had been under surveillance as recently as September for suspected ties to the jihadist scene, was shot dead by Italian police in a gunfight in Milan earlier today.

In the immediate aftermath of the Berlin attack, the AfD blamed Merkel's liberal border policy, under which more than one million asylum seekers entered the country since 2015, for posing a serious security threat to the country.

One party official, Marcus Pretzell, even called the victims 'Merkel's dead', in a tweet later criticised by the AfD leadership.

German Chancellor Angela Merkel prepares to deliver a statement in Berlin today

At a news conference on Friday, Merkel pledged a 'comprehensive' analysis of what went wrong, and rapid reforms.

However she stressed that Germany would not sacrifice its principles in the fight against terrorism.

'Our democracy, our rule of law, our values, our humanity - they are the alternative to the hateful world of terrorism, and they will be stronger than terrorism,' she said.

MERKEL: BERLIN MARKET ATTACK A 'TERRIBLE DEED' German chancellor Angela Merkel has said she was 'shocked and very saddened' by the Berlin Christmas market attack which left 12 dead and almost 50 injured, describing it as a 'terrible' deed. Speaking at a press conference Mrs Merkel said the government 'assumed' it had been a terror attack, adding that: 'We will find the strength to continue living life as we want to live it in Germany - in freedom, openness and together.' She said: 'It is a terrible deed which one cannot understand. It took their lives; many people are injured, are fighting for their lives and fighting for their health, and in these hours I first and foremost think of these people - the dead, the injured, their families, their friends, their relatives. German chancellor Angela Merkel has said she was 'shocked and very saddened' by the Berlin Christmas market attack which left 12 dead and almost 50 injured, describing it as a 'terrible' deed 'I would like you to know that we - all of us, the whole of the country - are with you in deep sadness.' A man thought to be the driver of the lorry that smashed through the Christmas market has been arrested and security sources believe he is a 23-year-old Pakistani asylum seeker who arrived in Germany in February, German media reported. He is believed to have lived at a refugee accommodation centre in a hangar at Berlin's old Tempelhof airport, which special forces police stormed overnight. Mrs Merkel said: 'We don't have anything for certain, but we must assume it was a terrorist attack. Speaking at a press conference Mrs Merkel said the government 'assumed' it had been a terror attack, adding that: 'We will find the strength to continue living life as we want to live it in Germany - in freedom, openness and together' 'It would be very difficult for us to learn that a human being committed this deed who came to Germany to ask for refuge and asylum. 'It would be terrible for all of the Germans who are very active day by day in helping asylum seekers and refugees. It would be repugnant for those that are helping people that have come to this country and are asking for our help.' She added: 'Millions of people, including myself, are asking ourselves, how can you live with the fact that, while celebrating the festive season where we want to celebrate life, somebody has come along and taken so many lives. I only know that we do not want to, and we cannot live with it. 'We do not want to allow ourselves to be paralysed by terror. It might be difficult in these hours, but we will find a strength to continue living life as we want to live it in Germany, in freedom and openness and together.' Advertisement

On Wednesday, a senior German politician has blamed the Christmas terror attacks on 'institutional political correctness', arguing that the suspect – a known ISIS fanatic who was on a deportation list – would not have been free to act if police had enforced the law.

The suspect, Anis Amri, 23, who was being monitored by police, would have been deported long ago if it wasn't for a liberal 'ideological agenda', he told MailOnline.

Hugh Theodore Bronson, the deputy leader of the Alternative For Deutschland party (AfD), said that German deportation law was ignored because the authorities were afraid of offending Muslims.

Hugh Theodore Bronson, the deputy leader of the Alternative For Deutschland party (AfD)

'The law as it stands is not being implemented,' he said. 'If it was, 12 people would still be alive, 48 people would not be in hospital, and there would have been no attack on Monday.'

Referring to the fact that the prime suspect, Anis Amri, had been arrested three times in Germany and was a known ISIS fanatic with weapons training who was due to be deported, Bronson added: 'There is a refusal by the authorities to implement German law.

'We are being too lenient in our implementation of the law. You can call it political correctness, you can call it an ideological agenda, but it cost 12 people their lives.

'I would be as bold as to say that if German law would be implemented as it should be, this attack wouldn't have happened.