The two men can be seen on security video that police released Monday — one of them brandishing a handgun and the other leaping over the counter.
As the second man leaped back over the counter at the TD bank in Toronto's west end, "he was tackled by a customer, at which time a struggle ensued," Staff Insp. Mike Earl said in a news conference.
At one point, the customer, a 54-year-old man, had the suspect in a headlock, he said.
The first man shot at the customer, but hit a 22-year-old teller in her thigh instead, he said.
The 54-year-old customer then chased the suspects into the parking lot, where he was shot in the abdomen, Earl said.
Both the customer and teller were still in hospital Monday, a day after they underwent surgery, and Earl said they were expected to survive.
However, it will take some time before police can speak to the customer, who had his kidney and pancreas partially removed and his spleen completely removed as a result of his injuries, police said.
The suspects made off with an undisclosed amount of cash, although it's believed a bank security ink device may have stained most of the money, police said.
The Canadian Bankers Association is offering a reward of up to $100,000 for information leading to the arrest and conviction of the suspects.
The actual amount paid will be determined by the police, depending on the information they receive.
"We hope this reward will lead to information needed to stop these criminals so that people can go about their lives freely and confidently," said William Crate, the association's director of security and intelligence.
The suspects are described as black men aged 20 to 25 with medium builds, wearing faded jeans, baseball caps and hooded sweatshirts — one with a number eight over the left breast, the other wearing a winter vest over top.
"These individuals are armed and dangerous, no doubt about it," Earl said.
Police said they took off in a stolen 1998 green Honda Civic, which has since been found and impounded.
Crate said there were 591 bank robberies in Canada last year, down from 1,100 in 2000.