HAMILTON - A teenage boy is in custody after allegedly assaulting a toddler with a weapon, leaving the little girl with "traumatic injuries" and sparking an hours-long standoff with police at a Hamilton home, officials said Wednesday.

Const. Jerome Stewart said officers were called to a home in the city around 3:30 a.m. after receiving reports of an injured child.

Outside the home, officers found a teenage girl with two children, including the 22-month-old girl, who was rushed to hospital where she remains in stable condition with serious injuries, officials said.

Stewart said the 16-year-old boy then barricaded himself inside the home, prompting a significant police response with the force's tactical team positioning an armoured vehicle nearby. A crisis negotiator was brought in to communicate with the teen and a mobile operations centre was set up nearby.

Around 11:30 a.m., tactical officers breached the home and apprehended the teen, who was then taken to hospital for an examination, police said.

"We are very happy we reached a successful outcome," Stewart told reporters.

There was no one else in the home at the time police went in, he said.

However as investigators searched the home, they found the family dog dead, police said in a later statement. Police believe the teen boy is responsible for the dog's death.

The teen was "known to the family," but Stewart wouldn't elaborate, citing the boy's age.

He said the teen may have suffered a minor injury during the incident.

"If he's treated and cleared from hospital, he'll attend the police station and then we'll conduct interviews if he wants to speak to police," Stewart said.

Hamilton paramedic Supt. Dave Thompson said the toddler suffered "traumatic injuries" and was in serious condition at the time they took her to hospital.

The standoff occurred near a high school., but Stewart said there was never any threat to the wider community.

"Right from the beginning, before the school was even open for business, we had the situation contained with the police presence," Stewart said.

Police provided few other details of the standoff.

—by Liam Casey in Toronto.

This report by The Canadian Press was first published Dec. 4, 2019.

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