Hackers launched a wave of sophisticated attacks on Wall Street firms in recent days, targeting information systems at major money managers, according to people familiar with the matter.

Point72 Asset Management informed investors on Wednesday that it had been attacked, though the hedge fund’s initial indications were that no client information was stolen, according to one of the people, asking not to be identified discussing non-public information. The firm told investors it was still reviewing the incident, the person said.

Attackers also attempted to infiltrate the information systems at other major hedge funds including, Millennium Management, Two Sigma Investments and Citadel as well as several private equity firms as part of the assault, the people said.