An elderly gunman opened fire inside a Minneapolis-area health clinic on Tuesday, wounding five people before police arrested the suspect, described by authorities as a disgruntled former patient who was well known to local law enforcement.
The suspect, identified as Gregory Paul Ulrich, 67, was taken into custody after the violence, which local media reported also involved an explosion inside the Allina Clinic in Buffalo, Minnesota, about 35 miles (55 km) northwest of Minneapolis.
Buffalo Police Chief Pat Budke told reporters hours later that he was unsure whether reports of an explosion were accurate, saying: "There may have been one prior to our going into the facility, but I can't confirm."
Bomb squad investigators called to the scene were examining a suspicious package found in the corner of the clinic's lobby, and additional "suspicious devices" were found at a nearby motel where Ulrich had been staying, said Wright County Sheriff Sean Deringer.
The sheriff cited records of "calls for service" relating to the suspect dating back to 2003, adding, "he's no stranger to law enforcement."
Based on known background, Budke said, investigators believe the gunman, a longtime Buffalo resident, acted alone and singled out the clinic over a personal grudge against the facility or its staff.
"The history we have as a department with this individual makes it most likely that this incident was targeted at this facility or at someone at this facility," Budke said, referring to an unspecified past "conflict" the suspect had with the clinic and "those who had treated him or attempted to treat him at the facility."
Five people wounded by gunfire were transported to area hospitals, Allina Health executive Kelly Spratt said at the news conference. Spratt declined to say whether the victims were clinic patients or staff. Their conditions were not immediately known, Spratt said.
Earlier, Minnesota Governor Tim Walz told a separate briefing he understood that "improvised explosive devices" were involved but did not say whether any had been detonated.
The Minneapolis Star Tribune, citing an emergency dispatch audio, reported that a bomb exploded in the clinic about 30 minutes after the shooting.
Live footage broadcast from the scene by Minneapolis television station KMSP-TV showed several windows at the front of the clinic had been shattered, and an empty wheelchair left on the sidewalk near the entrance.
Walz said the US Bureau of Alcohol, Tobacco, Firearms and Explosives, as well as the Federal Bureau of Investigation, were assisting in the probe of the incident.