NEW YORK Industrial and Commercial Bank of China (ICBC) injected significant capital into its U.S. unit to help settle trades after it was hacked this week and has hired a third party to make sure its systems are safe, three sources familiar with the matter said.

ICBC’s representatives told market participants on a call organized by industry group the Securities Industry and Financial Markets Association (SIFMA) that they hoped the assessment would be done as soon as this weekend, according to the sources, who added that some expected the assessment to take longer.

The rest of Wall Street has cut off the bank’s connection to their systems pending the review, the sources said.

The attack, confirmed by ICBC on Thursday, is the latest in a string of ransom demands by hackers this year. ICBC Financial Services, the bank's U.S. unit, said on Thursday it was investigating the attack that disrupted some of its systems, and making progress toward recovering from it.

SIFMA declined to comment. ICBC did not respond to a request for comment.

(Reporting by Paritosh Bansal and Lananh Nguyen; additional reporting by Carolina Mandl; editing by Megan Davies)