A candidate who is leading the race to become the mayor of Cologne, Germany was stabbed and seriously injured Saturday by a man who claimed to have anti-foreigner motives.

Henriette Reker was stabbed in the neck at a campaign stand, which was set up by Chancellor Angela Merkel’s Christian Democrats at a market. German Interior Minister Thomas de Maiziere warned the refugee crisis is leading to an escalation in hatred and violence.

Reker’s condition was stable, police chief Wolfgang Albers said.

Reker is an independent candidate in Sunday’s election for the new mayor of Cologne, Germany’s fourth-largest city. However, Reker is backed by Merkel’s conservatives and two other parties. The 58-year-old currently heads Cologne’s social affairs and integration department and is responsible for refugee housing.

Senior police investigator told reporters another woman was seriously injured and three people had minor injuries from the attack.

Wagner said the man who committed the act “wanted to and did commit this act because of anti-foreigner motives.” The 44-year-old suspect is a German national and a Cologne resident who had been unemployed for several years.

Prosecutor Ulf Willuhn said officials will now investigate whether that was in fact the man's primary motive or whether his health played a role. They plan to carry out a psychiatric examination.

Asked whether the suspect had specifically mentioned Reker's or Merkel's policies on refugees, Wagner said: "No. He made general statements in that direction — he didn't mention Ms. Merkel at all."

City officials said Sunday's election would go ahead as planned.

The suspect is in police custody but hasn’t been charged, a police spokesman told The Wall Street Journal. He will be brought before a judge on Sunday.

Maiziere described the stabbing as “an attack on our democracy and said he had long been “concerned by the hate-filled language and violent actions that accompany the refugee debate in Germany.”

"This cowardly attack in Cologne is further evidence of the increasing radicalization of the refugee debate," he said in a statement.

Cologne’s current mayor Juergen Roters called the stabbing “incomprehensible,” according to The Wall Street Journal.

“The city is holding its breath,” he said. Roters isn’t running for re-election.

Germany has taken in more refugees and other migrants than any other European Union country, and the influx is stretching its capacity to house newcomers. Most Germans have been welcoming, but there have been repeated attacks this year on refugee shelters, ranging from arson to racist graffiti.

Attacks on politicians are rare in Germany, but there have been prominent cases.

Then-Interior Minister Wolfgang Schaeuble was shot by a deranged man while campaigning in October 1990, an attack that left him using a wheelchair. A few months earlier, a mentally disturbed woman stabbed Oskar Lafontaine, then a prominent member of Germany's main opposition party, while he was campaigning in Cologne.

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The Associated Press contributed to this report.