Police smashed the biggest gambling network in Israel’s history in dozens of raids at locations in the center of the country on Wednesday morning.

According to Maariv, police swooped on the homes of 40 suspects early in the morning and brought them in for questioning. The suspects were scheduled to appear at the Tel Aviv District Court on Wednesday afternoon and police intended to ask they be remanded.

Authorities estimate that the gambling ring handled over a billion dollars over the past two years alone. As well as the homes of the suspects, police also raided money exchange kiosks in Tel Aviv, Holon, Herzliya, and Rishon Lezion, where they confiscated cash and paperwork.

A source told Ynet that it was the largest gambling chain discovered in Israel and one of the largest in the world.

At the heart of the operation was the Don-bet gambling website that focused its operations in Israel. The website featured extensive betting operations on soccer games, horse racing, and blackjack. Every day thousands of gamblers bet hundreds of thousands of dollars that were cleared through Israeli bank accounts. Some of the website’s servers were located in Israel and on Wednesday the site was unavailable due to “a site upgrade.”

The arrests come after an undercover operation conducted for over a year as a joint effort by income tax investigators, tax authorities, and money laundering investigators. Those arrested were involved in organizing the website, dealing with cash collections and providing technical services.