Aon Plc bought closely held Canadian firm Cytelligence Inc. to help boost its ability to respond to and investigate attacks on computer systems.

Aon picked up employees with cybersecurity consulting and digital forensic expertise, the London-based insurance brokerage and advisory firm said Tuesday in a statement that didn’t disclose terms. Cytelligence Chief Executive Officer Daniel Tobok will become the Canadian president at Aon’s cyber solutions group.

Aon is seeking to expand its foothold in the market helping companies deal with cyber attacks, which are expected to cost the world $6 trillion annually by 2021, according to a 2019 report from Cisco Security and Cybersecurity Ventures. Aon boosted the cyber group more than three years ago with the purchase of risk-management firm Stroz Friedberg, and now is adding Cytelligence employees based in offices in Toronto, Ottawa, New York, San Francisco and Miami.

“They have a very good capability that they have built in the digital-forensic and incident-response area,” J. Hogg, CEO of Aon’s cyber solutions group, said in an interview. The companies conducted at least one joint incident response together before the deal.

Merck & Co. and Target Corp. are among firms that suffered attacks or data breaches in recent years. Demant A/S, a maker of hearing aids, was the victim of a cyber attack in September, requiring it to take extreme measures to stop the issue from spreading, the company said.

Cyber risk has even trickled down to smaller companies that may have weaker defenses, Hogg said, without naming any clients.

Aon wants to keep expanding the business and plans to keep all employees on board, Hogg said. The company’s shares rose 1% to $227.18 at 10:28 a.m. in New York.