With around half the U.S. workforce working remotely, companies are experiencing an uptick in hacking attempts on their networks, according to The Wall Street Journal.

Before the pandemic, some firms tracked thousands, even millions of threats a day. As soon as workers headed home, companies started seeing attacks surge.

So far during the pandemic, Kraft-Heinz Co. has observed a jump of 10% to 15% in attempted email attacks, said Ricardo Lafosse, head of cybersecurity. Twitter Inc. saw hackers take over the accounts of several prominent users, including former President Barack Obama and musician Kanye West after tricking Twitter employees into sharing administrative information. Hackers have breached suppliers for financial services firms such as Freddie Mac and disrupted operations at hospitals in the U.S. and Europe.

As of May 28, the FBI had received around 320,000 complaints of internet crime, a senior official told the Senate Judiciary Committee in June — nearly double the rate for the prior year. A Secret Service official told the same hearing that he expects over $30 billion in stimulus funds will end up being pilfered through scams, many of them cyberattacks.