MAGDEBURG, Germany — German authorities said they received tipoffs last year about the suspect in a car attack at a Christmas market in Magdeburg as more details emerged Sunday about the five people killed.

Authorities have identified the suspect as a Saudi doctor who arrived in Germany in 2006 and had received permanent residency. Police haven’t publicly named the suspect, in line with privacy rules, but some German news outlets have identified him as Taleb A. and reported that he was a specialist in psychiatry and psychotherapy.

Authorities say he does not fit the usual profile of perpetrators of extremist attacks. The man described himself as an ex-Muslim who was highly critical of Islam and in many posts on social media expressed support for the far-right anti- immigrant Alternative for Germany, or AfD, party.

He is being held in custody as authorities investigate him.

“This perpetrator acted in an unbelievably cruel and brutal manner — like an Islamist terrorist, although he was obviously ideologically an Islamophobe,” Interior Minister Nancy Faeser said Sunday.

The suspect originally lived in the state of Mecklenburg- Western Pomerania, where he completed his specialist training in Stralsund and also came to the attention of authorities due to threatening criminal acts, the state interior minister, Christian Pegel, said Sunday.

In a dispute over the recognition of examination results, he threatened members of the state medical association with an act that would attract international attention, triggering an investigation and a search of his home, the dpa news agency reported, citing Pegel. No evidence was found of preparations for an attack, but a court found him guilty in 2013 of threatening an attack.

That was followed by other threats he made, Pegel said.

The head of the Federal Criminal Police Office, Holger Münch, said in an interview on the German broadcaster ZDF on Saturday that his office received a tipoff from Saudi Arabia in November 2023, which led authorities to launch “appropriate investigative measures.”

“The man also published a huge number of posts on the internet. He also had contact with various authorities, made insults and even threats. However, he was not known to have committed acts of violence,” said Münch, whose office is the German equivalent of the FBI.

He said the warnings proved to be unspecific.

The Federal Office for Migration and Refugees also said it received a tipoff about the suspect in the late summer of last year.

“This was taken seriously, like every other of the numerous tips,” the office said Saturday on X. But it also noted that it is not an investigative authority and that it referred the information to the responsible authorities. It gave no other details.

The Central Council of Ex-Muslims said in a statement that the suspect had “terrorized” them for years as it expressed shock at the attack.

“He apparently shared beliefs from the far-right spectrum of the AfD and believed in a large-scale conspiracy aimed at Islamizing Germany. His delusional ideas went so far that he assumed that even organizations critical of Islamism were part of the Islamist conspiracy,” said the statement.

The group’s chairwoman, Mina Ahadi, said in the same statement: “At first we suspected that he might be a mole in the Islamist movement. But now I think he is a psychopath who adheres to ultra-right conspiracy ideologies.”

Police in Magdeburg, the capital of the state of Saxony-Anhalt, said Sunday that those who died were four women ages 45, 52, 67 and 75, as well as a 9-year-old boy.

Authorities said 200 were injured, including 41 in serious condition. They were being treated in multiple hospitals in Magdeburg, which is 80 miles west of Berlin, and beyond.