A building on Chicago’s West Side collapsed on Tuesday morning after a nearby explosion, with reports of multiple injuries.

The building collapsed slightly after 9 a.m., according to fire officials. Multiple injuries occurred with authorities calling in at least 10 ambulances.

"Requesting manpower for searches in structure," tweeted the Chicago Fire Department.

“This is a confirmed explosion but source of explosion not known. ATF is on scene to assist. As is CPD bomb unit. Six transports so far searches underway. Three victims serious, two critical,” Chicago Fire Media tweeted.

Fire officials said that the explosion occurred at North Central Avenue and West End Avenue, with the building next door evacuated at 9:50 a.m., NBC Chicago reported.

With the cause of the explosion not immediately clear, local gas companies, Peoples Gas and ComEd, were called to the scene in case the explosion was gas-related.

Chicago Mayor Lori Lightfoot said on Twitter that she was closely monitoring the situation.

“My thoughts are with those who were injured and displaced in the building collapse in the Austin neighborhood. We must also thank the brave men and women of the Chicago Fire Department who are working to abate the dangerous conditions,” Lightfoot said.