Toronto police have detained and released at least one person of interest and continue to search for at least three other suspects, a day after two male students died during a brazen daytime shooting in Etobicoke.

The double shooting happened outside of the Toronto District School Board's School of Experiential Education, on McArthur Street across from Don Bosco Catholic Secondary School near Islington Avenue and Dixon Road, at approximately 12:30 p.m. on Monday.

Angela Gauthier, director of education for the Toronto Catholic District School Board, said police are offering support to students and teachers dealing with grief Tuesday. Pastoral staff are also available.

Students were "subdued," "respectful" and "shocked" on Tuesday morning, she said, adding that the morning routine nevertheless continued as normal with the singing of the national anthem and prayers.

Gauthier also said the school board will eventually conduct an analysis to determine if there was anything else they could have done to prevent the shooting.

Police spent the morning combing the scene and nearby apartment buildings for evidence. 

Toronto Catholic District School Board (TCDSB) trustee Maria Rizzo confirmed to CTV Toronto Monday afternoon that one of the shooting victims was a 15-year-old student from James Cardinal McGuigan, a Catholic high school located near Finch Avenue West and Keele Street. She said the other victim was also a student, but she did not know if he attended a TCDSB or Toronto District School Board high school.

Police will be conducting a post mortem to confirm the identification of the victims Tuesday.

Supt. Ron Taverner said police believe the shooting may have been a "targeted" incident but that the investigation was still in the preliminary stages.

"Obviously it is of great deal of concern that there are people out there with firearms that use them….We are working on trying to bring those individuals into custody," Taverner told reporters Monday afternoon.

'Bang, bang, bang'

Area resident Michael Snary was walking his dog at the time of the shooting. He said he saw a large group of what appeared to be young people -- some of them wearing Don Bosco uniforms -- headings toward a park located near where the two victims were found.

He said the group appeared to be fighting, before the shots rang out.

"Three gunshots, real fast – bang, bang, bang," Michael Snary," told CTV Toronto. "You'd think it was just going to be a fight, and kids will be kids, but then you hear the gunshots and it brings it to another level."

Police have not said if any Don Bosco students were involved in the shooting.

Anyone with more information is asked to call police at 416-808-2222.

With a report from CTV Toronto's Austin Delaney, John Musselman and Janice Golding