Updated | 15 injured in Ansbach explosion, attacker pledges allegiance to Daesh leader in video

While earlier reports outlined a gas explosion as the cause, Ansbach mayor Carda Seidel confirmed in a press conference that the blast was caused by an explosive device.

An unnamed Syrian man, who the police highly suspect to be the attacker, was the only person killed in the blast.

During a press conference, Seidel said 15 people were injured in the Ansbach attack, including four who are in a serious condition.

“No one suffered any life-threatening injuries,” she added, explaining that most of the injuries were mainly from splinters.

“Security measures were tightened after events of recent days, so that bag checks were introduced for Sunday night’s festival,” she said.

Earlier the state of Bavaria's interior minister Joachim Herrmann said the 27-year-old man had detonated the device after being refused entry to the music festival taking place at the Eugens Weinstube bar in the centre of the town because he had no ticket. He immediately detonated the explosives in his rucksack.

“Had he managed to get into the festival, there would certainly have been more victims,” Nuremberg’s deputy head of police, Roman Fertinger, said.

The explosion happened at about 10pm, near the entrance to an open-air music festival. Around 2,500 people in attendance were evacuated. The festival was shut down as a precaution after the explosion. 

Herrmann said the man’s request for asylum was rejected a year ago, but he was allowed to remain in Germany on account of the situation in Syria. “It’s terrible ... that someone who came into our country to seek shelter has now committed such a heinous act and injured a large number of people who are at home here, some seriously,” he said.

According to German interior minister Thomas De Maizière, the attacker had been given refugee status in Bulgaria which is why his application in Germany was refused. A deportation order was suspended because of the suspect's mental health problems.

According to authorities, the man had a history of making attempts on his life, while AFP reports that he had spent time in a psychiatric facility. It quotes Reinhold Eschenbacher, a social worker who knew him, saying he was “friendly, inconspicuous and nice”. Eschenbacher had encountered him when he came to his office to pick up his welfare benefits.

Speaking to Deutsche Press-Agentur, Herrmann said his personal view was that the attack was likely the work of an “Islamist” suicide bomber

“My personal view is that I unfortunately think it is very likely this really was an Islamist suicide attack. The obvious intent to kill more people at least indicates an Islamist background.”

He told Reuters the recent attacks in Germany raised serious questions about the country’s asylum law and security nationwide. The Guardian reports that he planned to introduce measures at a meeting of Bavaria’s conservative government on Tuesday to strengthen police forces, in part by ensuring they have adequate equipment. 

While there has been no claim of responsibility for the Ansbach attack by daesh, a video found on the perpatrator's phone shows him pledging allegiance to the group's leader, Abu Bakr al-Baghdadi, Associated Press and Al Jazeera report citing Bavaria's top security officials.

Herrmann said that according to an initial translation of the Arabic-language video, the 27-year-old man announced a “revenge” attack against Germany. "The video strongly suggests the bombing was a “terrorist attack”," he told reporters.

Herrmann added that officers discovered videos with “Salafist content” on storage devices seized at the 27-year-old Syrian man’s home. Police also found petrol, chemicals and other material that could be used to make a bomb. He said there was no evidence yet of any links to extremist organisations but that the evidence found suggested an Islamic extremist motivation.

Herrmann also pointed to the perpetrator’s backpack which he said contained metal items used in “wood manufacturing” and could have killed many more people.

“It’s a further, horrific attack that will increase the already growing security concerns of our citizens. We must do everything possible to prevent the spread of such violence in our country by people who came here to ask for asylum,” Herrmann added.

De Maizière said that possible links with Daesh could not be ruled out from the investigation, but the attacker’s mental health may also have been a factor. "Unstable people are vulnerable to radicalisation," he said, "both things could also have contributed. But the investigation is at the early stages."

The recent attacks in Germany have garnered criticism towards chancellor Angela Merkel.

Hans-Olaf Henkel, an MEP for the centre right Alliance for Progress and Renewal, criticised Angela Merkel’s open refugee policy in the wake of a week of violence.

“This welcome policy of Frau Merkel has definitely incited thousands, if not hundreds of thousands of people to take this risky route, from rather safe camps to come to Europe in the first place. So she must be blamed for the fact that a lot of refugees came because they got the impression that they were welcome by Germany,” he said, speaking to BBC Radio 4’s World at One programme. “This policy has clearly divided Europe. There is not a single head of state of state or government in Europe who follows the policy of Frau Merkel,” he added.

Henkel claimed Merkel’s policy had contributed to the UK’s vote to leave the European Union. “I followed the Brexit discussion in the UK and I noticed in the last couple of weeks of the debate, the discussion about immigrants got really in the forefront. I have noted that [Nigel] Farage and [Boris] Johnson could make a point by saying ‘look these refugees, which Germany now takes, will be integrated and once they have a German passport they can show up in London’. I was against Brexit but I’m afraid Frau Merkel’s policy had something to do with the result of Brexit referendum.”

On the other hand, when De Maizière was asked whether the attacks were proof that Merkel’s refugee policy was wrong or showed her slogan “we can manage it” was too optimistic, he pointed out that none of the attackers so far named - Würzburg, Munich, Reutlingen or Ansbach - were among the refugees who arrived last autumn after Merkel’s declaration that Germany’s doors were open to those in need. "Therefore her policy could not be held responsible," De Maizière said.

German MP Stephan Mayer, who is home affairs spokesman for Angela Merkel’s CDU parliamenary group, also rejected claims that Germany’s acceptance of so many refugees was to blame for the spate of attacks. He accepted that there “is a lot of space for improvement” in the way Germany deals with the influx of migrants, but added that “it is completely wrong to blame Angela Merkel, or her refugee policies, for these incidents.”

In the meantime, Reuters cites German newspaper Neue Osnabruecker Zeitung which says Germany’s federal criminal police have 410 leads on possible terrorists among refugees.

Investigations have been launched in 60 cases, the newspaper said. It cited federal BKA police as saying they did not currently have any concrete indications of attack plans.

“In view of continuing migration to Germany we must assume that there could be active and former members, supporters and sympathisers of terrorist organisations or Islamist-motivated war criminals among the refugees,” the newspaper quoted federal police as saying.