A US-Israeli teenager accused of making hundreds of threatening calls to Jewish centres in the United States also allegedly tried to extort a US lawmaker, an indictment filed Monday said.

The teenager arrested in southern Israel last month following an international investigation allegedly told a Republican senator to take back statements he made to the media or be penalized financially, according to the indictment filed in a Tel Aviv court on Monday.

After the politician did not respond, the suspect bought drugs on the internet and sent them in envelopes to the lawmaker's house in order to frame him, according to police spokeswoman Luba Samri.

The 18-year-old made threats against more than 2,000 institutions, including police stations, schools and airlines, resulting in schools and other places being evacuated, several flights being cancelled, and an emergency landing in one case, according to the indictment.

Israeli media reported over the weekend that Israel has ignored US Justice Department requests to extradite the teenager, whose identity is under gag order, in order to prosecute him in Israel.

The hacker was arrested last month after a trans-Atlantic investigation with the FBI and other international law enforcement agencies. U.S. Jewish groups welcomed the breakthrough in the case, which had drawn condemnation from President Donald Trump.

Since the beginning of 2017, Jewish centres in some 20 US states, stretching from Colorado to New York, had reported receiving more than 100 hoax bomb threats, according to US media outlets.