BERLIN (AP) — The online magazine of the Islamic State group has described how a 27-year-old Syrian asylum-seeker who blew himself up at a bar in the southern German town of Ansbach spent months planning the attack, once even hiding his home-made bomb in his room moments before a police raid.

The weekly Al-Nabaa magazine's report, published late Tuesday, added that Mohammad Daleel had fought both in Iraq and Syria with a branch of al-Qaida and the IS group before arriving in Germany as an asylum-seeker two years ago.

Daleel died and 15 people were wounded when the bomb exploded in a wine bar Sunday night after he wasn't allowed entry to a nearby open-air concert because he didn't have a ticket.

The Ansbach attack was the last one of four attacks in the country in the span of a week, two of which have been claimed by the Islamic State extremist group.

The attacks have left Germany on edge and Chancellor Angela Merkel's policies of welcoming refugees under renewed criticism.

Conservative lawmakers have called for an increased police presence, better surveillance and background checks of migrants and new strategies to deport criminal asylum seekers more easily.

Al Nabaa's Arabic-language report on the attacker said he initially fought against government forces with al-Qaida's branch in Syria before pledging alliance to IS in 2013.

He also helped the group with its propaganda efforts, setting up pro-IS accounts online.

In Germany he started making the bomb, a process that took him three months, al Nabaa wrote.

It added that German police once raided his asylum shelter in an unrelated case and searched Daleel's room without noticing the bomb that he hid moments before the raid.

The IS group earlier claimed the Ansbach attack, publishing a video it said of Daleel pledging allegiance to the group and vowing that Germany's people "won't be able to sleep peacefully anymore." It appears to be the same video as the one found by German investigators on the suicide bomber's phone.

Daleel unsuccessfully applied for asylum in Germany and was awaiting deportation, German authorities said.

The unprecedented bloodshed in Germany began July 18, when a 17-year-old from Afghanistan wielding an ax attacked people on a train near Wuerzburg, wounding five people before he was shot to death by police. The Islamic State group claimed responsibility.

The deadliest attack came Friday night in Munich. The German-born, 18-year-old son of Iranian refugees went on a shooting spree and killed nine people. The youth had obsessively researched mass shootings, and authorities said the attack does not appear to be linked to Islamic extremists.

On Sunday, a 21-year-old Syrian used a machete to kill a 45-year-old Polish woman in the southern city of Reutlingen. Authorities said assailant and victim knew each other from working in the same restaurant, and the incident was not related to terrorism.

Despite the fact that not all the cases were terror-related, they have caused concerns about the government's migration policy that saw more than 1 million people enter Germany last year.

A senior figure in the nationalist Alternative for Germany party, which has no seats in the national parliament but saw its popularity surge after last year's migrant influx, suggested Wednesday that there should be "a halt to immigration for Muslims to Germany" until all asylum-seekers currently in the country have been registered, checked and had their applications processed.

"For security reasons, we can no longer afford to allow yet more Muslims to immigrate to Germany without control," Alexander Gauland, a deputy party leader, said in a statement. "There are terrorists among the Muslims who immigrated illegally and their number is rising constantly."

The Interior Ministry rejected the notion that Germany is still seeing uncontrolled migration. Spokesman Johannes Dimroth said that "for some time" all new arrivals have been registered and checked against security databases.

"As for the concrete question of whether you can act differently according specifically to a person's religion, as I understand it that simply would be incompatible with our understanding of freedom of religion," he said.

German train operator Deutsche Bahn said Wednesday that following the attacks it would invest heavily in increased security and hire hundreds of security staff to control trains and train stations across the country.

The city of Munich said it is re-evaluating its security concept for the annual Oktoberfest and is considering banning all backpacks from the popular beer fest.

Mroue reported from Beirut, Lebanon. Geir Moulson contributed from Berlin.