What began as a 911 medical emergency call turned into a multiagency hazardous materials scare Friday, resulting in tenants of at least six apartments in the Marcy Holmes neighborhood of Minneapolis being evacuated for about 10 hours.

First responders arrived just after 8 a.m. and entered the apartment where the medical emergency was reported, but quickly noted signs of what they believed were hazardous materials.

Responders including a bomb squad, a National Guard civil support team and a chemical assessment crew cleared the building and cordoned off an area of several blocks near the intersection of 6th Street and 5th Avenue SE. to help firefighters enter the apartment building, Minneapolis police spokesman John Elder said. Air samples were taken throughout the day.

A man at the residence was taken to an area hospital, Elder said, but he could not confirm whether he was injured or somehow contaminated.

Around 6:30 p.m., Elder announced that authorities believed they were not dealing with a hazardous substance, but did not rule out whether a chemical compound was involved.

After teams had determined the other five apartments were safe, residents of those units were allowed back into the building. The apartment where the incident occurred will remain sealed for further investigation.

"These people who had nothing to do with this call at all have been greatly inconvenienced and have actually been very good about it," Elder said of the displaced tenants, some of whom are University of Minnesota students.

One student tenant who was waiting to get back into his apartment late Friday said he did not want to discuss the incident.

During the daylong drama, rescue teams wore hazardous materials suits, and several were seen being decontaminated or washed off upon leaving the building. At one point, several rescue workers in suits emerged holding a bag of evidence that appeared to include documents and books.

The red brick building is owned by T. Lynn Chilgren Properties. Company officials declined to comment Friday evening.

The six apartments house multiple tenants, Elder said, but a total number of evacuees was not available. A Metro Transit bus arrived at the area early in the day to move residents to an undisclosed location. Emergency vehicles from various agencies came and went as the testing and contamination investigation continued.

Liz Sawyer • 612-673-4648

Anne Millerbernd is a University of Minnesota student on assignment for the Star Tribune

Anne Millerbernd • 651-308-7126