A top Saudi hacker who targeted Israel and Jews has died at age 28, Saudi media reported Sunday. The man, who was not named, died of an asthma attack brought on by summer sandstorms.

The hacker, who called himself “Cyber Terrorist,” was known for hacking well-protected sites including Microsoft. He targeted Jewish and Israeli sites in particular, as well as a site belonging to Danish cartoonists who drew cartoons of Mohammed.

A fellow Saudi hacker calling himself “hell cyber” told the media that “Cyber Terrorist” had put “defending Islam and the Prophet” as his top priority.

“One company had shown interest in working with him for a large sum of money, but he rejected the offer because it came from a Jewish company,” he related.

Israeli experts have warned that cyber warfare, already an active part of the Israeli-Arab conflict, will become more important with time. While Arab hackers have so far created financial problems, in the future enemies could crack Israeli military or healthcare systems, they say.

A second Saudi hacker, calling himself OxOmar, gained notoriety in Israel for attacking the El-Al website and stock exchange and publishing the details of thousands of Israelis’ credit cards.