Haaretz wondered if Hamas was behind this and made a lot of money from these bets.

It added that major betting operations took place against Israel in Tel Aviv and Wall Street financial markets, days before the October 7 attack.

She stressed that these bets made billions of dollars.

Some apparently knew in advance about Hamas's plan for the attack, which plunged into financial markets.

The newspaper said the movement may have benefited financially from the matter.

A study published in the United States concluded that Hamas may have tried to profit financially from its attack on Israel by using prior knowledge of the attack to conduct major short sell-offs of shares prior to the attack.

The study, published in the journal SSRN and by researchers at New York and Columbia Universities, found that investors who knew in advance of the attack made billions of dollars, according to their financial behavior.

As soon as the news broke, Israeli authorities opened an investigation into the matter, Reuters reported on Monday.

In response to a question about the matter, the Israel Securities Authority said: "The matter is known to the authority and is under investigation by all parties involved."

In their study, the researchers stated that they documented a significant rise in short selling in dozens of companies traded on the Tel Aviv Stock Exchange.

This sudden rise was very large on October 5, five days before the attack.

According to the researchers, short selling was more than in many crises, such as the recession that followed the financial crisis, the 2014 war and the coronavirus crisis.

Short selling is a common selling technique on the stock exchange that relies on investors' expectation of a decline in the price of shares, and is seen as a profit-generating strategy, by selling shares at a high price and then buying them back at a cheaper price.