A 3-year-old boy was struck and killed by gunfire in a northeast Minneapolis apartment complex on Monday.

Police officers from Minneapolis' Second Precinct responded to the "child shot" call at Hook & Ladder Apartments in the 2300 block of Jefferson Street NE. around 12:45 p.m., where they located the young boy with critical injuries. He was suffering from a gunshot wound to the top of the head, according to a source with knowledge of the incident.

Paramedics rushed the toddler to HCMC, where he died a short time later.

In a brief news conference, assistant police chief Christopher Gaiters told reporters that investigators remain on scene "working diligently to find out what happened to this child."

He could not say whether police believe the shooting was accidental or intentional. Gaiters declined to confirm what evidence, if any, was collected or comment on the circumstances preceding the gunfire.

When asked whether authorities have reason to believe the boy may have shot himself with an unsecured firearm, he replied that they simply don't know yet.

"At this point, it is unclear how many shots were fired or what type of gun" was used, Gaiters said, noting that the boy was inside the residence with at least one adult present, who made the initial 911 call. "We're going to work with the public, we're going to work with the family; it's a very difficult time."

No arrests had been made in the case as of Monday afternoon.

As of Sept. 30, police tallied at least 33 juvenile shooting victims in Minneapolis this year. The average age of those struck by gunfire dropped to 15 — the lowest age in more than five years, according to MPD data.

Nationwide, gun violence remains the leading cause of death for children.

Approximately 200 minors picked up a firearm and accidentally shot themselves or someone else in the United States this year, resulting in 74 deaths and 128 injuries, according to a database compiled by the gun-control advocacy group Everytown USA.

Of those, at least two occurred in Minnesota, including one case in which a 17-year-old boy unintentionally shot and killed his 16-year-old friend with a ghost gun inside a New Hope home last month. The older teen has since been charged with first-degree assault and illegal possession of a machine gun.

In another case last April, an 11-year-old boy was shot and wounded by his 13-year-old cousin in St. Paul after a group of kids discovered two unsecured firearms in their father's closet drawer. The kids were playing with the handguns, assuming they were unloaded.