Niagara Regional Police Service says a 43-year-old man is wanted for first-degree murder in connection with the death of his stepson.
Niagara Police said officers responded to a call at 10:16 a.m. Friday after receiving a report that a child was in medical distress at a Queenston Street property.
Justin Kuijer’s seven-year-old stepson Nathan Dumas was found critically injured, and died in hospital on Saturday.
Police have not confirmed the cause of death.
Police were already looking for Kuijer in connection with the stabbing of an RBC employee who was sent to hospital on Friday.
The suspect entered a Royal Bank branch on Martindale Road just before 10:30 a.m. and assaulted a female employee with a weapon, according to police.
The man fled the scene in what is believed to be a 2009 Pontiac Montana minivan, licence plate BYTE 392.
Police said the woman was taken to hospital in serious condition, but is currently stable.
The female victim and Kuijer were known to each other professionally, police said.
It is unclear if there is a connection between Dumas and the female victim.
Kuijer is considered armed and dangerous. Anyone with information is being asked to call 911 or Crime Stoppers anonymously at 1-800-222-8477 (TIPS).
St. Catharines police constable Philip Gavin says a Canada-wide warrant for Kuijer will be issued Monday.
With files from The Canadian Press