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MAINZ, Germany — Police will flood German streets this week during Carnival celebrations amid efforts to beef up security after a massive sex-assault spree and an elevated terror-threat level.

More than 2,000 police officers and 350 cadets — double the number last year — will be on duty when the annual Carnival kicks off this week in Cologne, where more than 1,000 women reported being attacked on New Year. Most of the attackers were allegedly of North African origin, sparking anti-foreigner sentiment and a backlash against Germany's country's asylum policies.

“This dimension of crime and especially sexually motivated attacks on girls and women, which also happened in other cities, has caused a high level of insecurity,” Cologne Mayor Henriette Reker said at a press conference earlier this week.

German federal police patrol the main railway station in Cologne, Germany Monday. Oliver Berg / EPA

German security officials were also operating under "an abstract and high" terror threat level.

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"There is no place for any form of violence during Carnival,” Juergen Mathies, head of Cologne police, said at the press conference. Police would pursue any form of crime, “including people who sexually attack women and do not take no for an answer," he added.

Cologne also plans to boost video surveillance and set up a “security point" for women staffed by social workers and psychologists. Officials, who expect around 1 million costumed and masked revelers to descend on the city, said they planned to illuminate 30 "dark areas" of town with extra floodlights and close off a square that could not be lit properly.

Related: Germany to East Deportation Laws After Sex-Assault Spree

While Carnival season started in November, street celebrations kick off on Thursday with Women's Day Carnival and end on Feb. 9.

The hundreds of attacks in the early hours of Jan. 1 led to a huge spike of sales in defense sprays and non-lethal weapons. They also piled pressure on the government of Chancellor Angela Merkel who has pushed to allow more than 1 million asylum seekers to enter the country.

Authorities were conscious that the raucous and sometimes bawdy Carnival celebrations might confuse some recent arrivals to Germany.

To help foreigners — especially those who came as refugees from Syria, Iraq and Afghanistan — navigate the so-called crazy days, Carnival organizers in some cities distributed flyers with a code of conduct in German, English and Arabic.

A police officer hands out information leaflets advising on social etiquette for refugees ahead of the Carnival season at a refugee camp in Mainz, Germany, on Monday. Kai Pfaffenbach / Reuters

Flyers distributed in Bonn emphasized that people must “treat each other with respect and observe the law,” despite the fact that during carnival people make fun of each other “without fear of punishment."

"'Butzen’ means kissing somebody on the cheek, one of our carnival customs,” the flyer added, stressing that sexual “overtures” are strictly prohibited and that “women and men must always consent to the ‘butzen.’ No means no!”

Carnival is a treasured tradition in cities like Cologne, Dusseldorf and Mainz in Germany’s Rhineland region. Along with the costumes and generalized revelry, satirical floats mock politicians and global events. One of the floats in Monday’s Cologne Carnival street parade will show "Mother Colonia" shedding tears over her broken rose colored glasses, symbolizing the city’s distress over the loss of an ideal world.