A string of devastating bank hacks across Latin America all carry North Korean fingerprints, according to three people with knowledge of the matter.

The FBI on Monday announced the arrest of 74 people across three continents for hijacking bank transfers using email fraud.

A forthcoming cybersecurity strategy from the Department of Homeland Security will seek to curb “systemic risk” to critical infrastructure by helping to secure digital tools used across sectors, DHS Secretary Kirstjen Nielsen said.

Mick Mulvaney revealed Thursday that the agency had suffered some 240 “lapses” in data security over an unspecified time period, in addition to a suspected 800 other such incidents.

The unanimously approved guidance details the ways in which publicly traded companies ought to be transparent with investors and other stakeholders when it comes to cyber risk.

Just three of the corporate victims lost more than $300 million, according to prosecutors.