A 16-year-old student was arrested Thursday for allegedly bringing down Miami-Dade County Public Schools’ (M-DCPS) virtual learning platform, which had been down for several days. According to the M-DCPS, district detectives traced the IP address responsible for the attacks to the student, who is a junior at South Miami Senior High School.

“The student admitted to orchestrating eight Distributed Denial-of-Service cyber attacks, designed to overwhelm District networks, including web-based systems needed for My School Online. The student used an online application to carry out these attacks and has been charged with Computer Use in an Attempt to Defraud. A 3rd-degree felony and Interference with an Educational Institution — a 2nd-degree misdemeanor,” the district — the fourth-largest in the country — said in a statement that did not name the student.

According to the district statement, it faced several connectivity issues resulting from both a malicious cyberattack and software malfunction, which it attributed to a problem with software provided by Cisco Systems.

Colleen Wright of the Miami Herald reported that The M-DCPS superintendent said that some of the attacks on its systems emanated from outside the U.S.

Justin Cappos, an associate professor in the Department of Computer Science and Engineering at the NYU Tandon School of Engineering, was skeptical about the attack coming from groups outside the U.S. and noted that Miami-Dade school district had been having problems with its system before the hack.

“So it means that they’re not doing basic cybersecurity hygiene. They’re not applying patches; they’re not updating software,” he said.

“They were having problems because they had outdated systems, and they knew they needed to do an update to fix this. After they applied their update, they noticed that they had capacity problems and started to notice this denial of service.”

Cappos tells Yahoo Finance that other school districts around the U.S. could be just as vulnerable as the Miami-Dade County Public Schools.