Authorities will be on increased alert for any threats to Chicago mosques after shootings that left at least 49 people dead at two mosques in New Zealand.

“Special attention will be given to Chicago mosques as a precaution,” the Chicago Police Department wrote in a tweet. Officials added there were “no known threats” to the city.

Mayor Rahm Emanuel said an attack on any place of worship is “an attack on all places of worship.”

“It shouldn’t be lost on anyone that, following the attack on the synagogue in Pittsburgh, the first community that spoke up and offered support was the Muslim community. The first group that offered financial support was the Muslim community. I want all of our Muslim brothers and sisters to know that Chicago welcomes them and welcomes their sincerity of prayer for our common humanity,” said Emanuel.

The Cook County Department of Homeland Security and Emergency Management is asking members of the public to be on the lookout for suspicious behavior, including vehicles parked in odd locations or unattended packages or bags.

“Our residents are our first line of defense in identifying and reporting any threats to public safety,” DHSEM Executive Director William Barnes, said in a statement. “Always be aware of your surroundings and do not hesitate to alert authorities to anything that appears unusual or out of place.”

Anyone who notices unusual items or suspicious people watching or gathering information about facilities is asked to call the department’s “If You See Something, Say Something” anti-terrorism campaign at (855) 777-8274.

The Council on American-Islamic Relations on Friday called for increased security at mosques, schools and community centers.

“In the wake of this tragedy, we urge mosques, Islamic schools and other community institutions in the United States and around the world to take stepped-up security precautions, particularly during times of communal prayer,” CAIR National Executive Director Nihad Awad said in the statement.

CAIR condemned “the apparent anti-Muslim hate and anti-immigrant hate that motivated the attacks.”

The Council of Islamic Organizations of Greater Chicago also condemned the attacks in a statement and called for the international community to “renounce any ideology that seeks to justify the murder of any group of people based solely upon their faith.”