Ch Supt Scott Cowie, area commander for Sunderland, said: “The last 24 hours have brought unimaginable agony and heartbreak for the loved ones of Luke, Jackson and Zara.
“All three had their whole futures ahead of them and will be hugely missed.
“We also recognise the impact that this tragedy has had upon the people of Sunderland and further afield, and know that you will continue to be there for one another.”
Earlier, a spokesperson for Sunderland College said they were “deeply saddened” by the deaths of three of their students and offered condolences to their families and friends.
“This is a heartbreaking loss for our college community, and the wider city of Sunderland,” a statement published on Facebook said.
Cowie asked the public not to speculate on the circumstances.
“In doing so, please be mindful of the potential impact such commentary could have on the families of those involved in this incident,” he said.
The force has asked anyone with information to get in touch.
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