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The University of Guelph campus in 2020. Police responded to approximately 550 incidents across Guelph that Saturday, including about 250 directly related to homecoming.Melissa Tait/The Globe and Mail

A new report shows as many as 15,000 people gathered on a Guelph, Ont., street during an unsanctioned homecoming party last month, prompting a police response that cost more than $90,000.

A report presented to the Guelph Police Service Board Thursday details the scale of the Sept. 26 gathering on Chancellor’s Way near the University of Guelph.

It says police responded to approximately 550 incidents across Guelph that Saturday, including about 250 directly related to homecoming.

That’s more than double the roughly 250 incidents police typically handle on a Saturday.

The report says the police response involved approximately 88 officers and civilian members – and hundreds of hours of overtime – with the cost totalling about $91,000.

University of Guelph pledges action after out-of-control homecoming parties

It says police made six arrests during the event, including four for public intoxication, one for assault and one for causing a disturbance.

About 70 provincial offence notices were also issued that day, mostly liquor-related, the report says.

Videos from the off-campus homecoming party showed massive crowds of young people in the streets, with some throwing bottles and other objects as police officers tried to control the situation. Police said officers were also dealing with people climbing buildings, as well as shoplifting and vandalism at nearby businesses.

University of Guelph president Rene Van Acker said the party risked the safety of students and neighbours and the university was reviewing the incident.

Guelph police said earlier this month that they’re establishing a “homecoming working group” to manage large unsanctioned gatherings in the future. The group includes the city, the University of Guelph and Guelph General Hospital.