JERUSALEM, Sept. 23 (Xinhua) -- Israeli police arrested Sunday four Jewish men accused of cooperating in the kidnapping of an Eritrean migrant in an extortion ring which leads to Hamas and Sinai-based militants.

The four men, who accused of acting as the contact between an East Jerusalem Arab and the family of the kidnapped man living in Tel Aviv, were extorting 15,000 U.S. dollars, said the police officials Sunday.

Israeli police traced the East Jerusalem man, Luai Nasser Al- Din, who sent the money to Hamas in Ramallah after receiving it from the four Israelis, for a month after they found large amounts of money being transferred to Hamas in Ramallah from Jerusalem.

Police believe that this kidnapping case is part of a larger operation, The Jerusalem Post reported.

The four Netanya-area Israelis, including one minor, told police that they were not aware that the money was sent to Hamas, which was doubted by the police.

Al-Din's attorney, Leah Tsemel, denied all the accusations against her client. "He denies everything, absolutely everything, and claims that the amount of money in his possession is very small. He denies receiving money from these men," Tsemel told local media on Sunday.

Although it is the first such case involving Jewish Israelis, many African migrants who tried to cross into Israel via the Sinai are held hostages by Bedouins on the peninsula who then contact their families for ransoms.