Somebody spray-painted "Don't spread Islam in the Czech Republic! Otherwise we'll kill you" on the mosque in Brno, Czech Republic. This photo was taken on 3 January 2020. (PHOTO: http://www.islamonline.sk/)

Somebody has spray-painted graffiti reading "Don't spread Islam in the Czech Republic! Otherwise we'll kill you" on Brno's only mosque.

Police have been investigating the crime since Friday afternoon, spokesperson Bohumil Malášek told the Czech News Agency (ČTK). The mosque on Vídeňská Street has been the target of attack several times before.

"We have documented this case and we are investigating information that could lead us to the perpetrator," Malášek said. According to him, officers are investigating the affair as one of vandalism.

The chair of the Headquarters of Muslim Communities in the Czech Republic, Muneeb Hassan Alrawi, told ČTK this recent attack had been preceded by a longer period of calm. "We reported this to police as soon as we discovered it," he said.

"We are taking it seriously as a direct threat, this is not an anonymous outcry on the Internet. It is necessary to see this in the light of attacks on mosques worldwide and what I would say is, overall, a difficult atmosphere and mood in the Czech Republic," Alrawi said.

Previous attacks on the mosque escalated after 2015, when the "migration crisis" was at its height and hundreds of thousands of asylum-seekers were flowing into Europe; this most recent case has happened at a time of increased international tensions after the US assassination of Iranian Major-General Qasem Soleimani. According to news server Islamonline.sk, this is the eighth incident to target the Brno mosque in the last five years.

In December 2013 somebody hung a piece of pork on the mosque's front door and scattered pork bones in front of the entrance. In August 2015, someone broke the mosque's windows using an iron rod, and three months later somebody poured what was probably motor oil over the entire front door and facade.

On another occasion someone spray-painted anti-Muslim slogans on the exterior and broke through the front door. In September 2015, several members of the Workers Social Justice Party (Dělnická strana sociální spravedlnosti - DSSS) assembled in front of the mosque.

Those perpetrators stuck their party's insignia to the front door and verbally assaulted the Muslims who were present. In 2016, anonymous vandals put a bag with a pig's head in front of entrance to the mosque.

That same year about 100 opponents of Islam also assembled in front of the mosque, led by Martin Konvička, to eat pork and drink alcohol. After that the Muslim community installed security cameras on the mosque out of fear of more attacks, and they remain operational.

Brno's mosque opened in 1998 and Muslims regularly gather there for prayer. The mosque sparked protests even before it ever opened.

The Islamic Foundation in Brno originally wanted a small tower on the building, symbolizing a minaret, but eventually backed away from that idea after the protests. A green mosaic featuring a religious text is therefore all that has been placed above the front door of the place of worship.