SAN FRANCISCO (USA TODAY) — A New Jersey man has pleaded guilty to computer crimes charges for an online attack that caused a massive Internet outage last year, according to federal court documents unsealed Tuesday.

The Justice Department says Paras Jha built the Mirai botnet, which operated hundreds of thousands of infected household devices to flood websites with traffic, knocking out services such as Netflix and PayPal. The plea agreement was filed Dec. 5 in federal court in Alaska.

Dalton Norman and Josiah White were charged with helping Jha and also pleaded guilty last month.

The plea agreement says Jha and his cohorts built the botnet to launch denial of service attacks against business competitors and others against whom they held grudges and to make money from renting the botnet to others. They also wanted to extort money from companies that either were under attack or wanted to avoid being attacked, it said.

The Mirai botnet infected Internet-connected devices with malicious software to launch a series of attacks on websites. Among the targets was an Internet infrastructure firm, Dyn.

The program allows even unskilled hackers to take over Internet-connected devices and use them to launch distributed denial of service, or DDoS attacks. The software spreads via the Internet, taking over DVRs, cable set-top boxes, routers and even Internet-connected cameras used by stores and businesses for surveillance.

In the past, such DDoS attacks were accomplished by hijacking computers with malicious software and turning them into a robot network, or botnet, that sent the messages.

Mirai and other software available online now focus on compromising devices that are connected to the Internet but that most consumers don’t think of as computers, the so-called Internet of Things.

Jha and his cohorts made more than $180,000 leasing access to others who made money by directing fake Internet traffic to ads on infected websites, the plea agreement says.