The heist was carried out with a secrecy that Banksy himself might have admired.

Around 5 a.m. on Sunday, a man sneaked into a Toronto warehouse wearing a black jacket, a green camouflage baseball hat and bluejeans. There, an exhibition of 80 prints and other artwork by the publicity-averse street artist and prankster was being readied for a coming show.

The man padded across the concrete floor, lifted a print of “Trolley Hunters” off the wall, and breezily walked out the door he came in. He was caught carrying the $38,000 print on surveillance video, which the Toronto Police Service distributed on Thursday.

Corey Ross, the president of Starvox Entertainment in Toronto and a producer of the exhibition, “The Art of Banksy,” said staff members became aware of the theft when they came in that morning.

“I don’t know who did it or why,” he said. He denied that it was a publicity stunt ahead of the exhibition’s opening. All of the works are on loan from collectors who either bought them online or at a Banksy show.