Israeli police arrived on Friday at Prime Minister Benjamin Netanyahu's home where media reports said they were to question him for an eighth time over allegations of fraud and bribery.

An AFP journalist saw police arriving at Netanyahu's official Jerusalem residence in two vehicles at around 9 am (0700 GMT).

Police issued no official confirmation that questioning was under way.

Investigators were at the same time to take a statement from his wife Sara at national fraud squad headquarters near Tel Aviv, media said.

A former Netanyahu aide and a top businessman are both in custody, linked to allegations of suspected fraud by the premier.

Nir Hefetz, a former media adviser to the Netanyahu family, and Shaul Elovitch, the controlling shareholder of telecoms group Bezeq, were among seven suspects arrested last week as fraud suspicions against Netanyahu snowballed.

Police suspect Elovitch was given business concessions in return for Netanyahu receiving good press on Walla!, a news website he owns.

New arrest reported

In addition, Israeli army radio said Friday that "a former senior communications ministry official close to the prime minister was detained this morning for questioning in the Bezeq affair."

He was not named.

Channel 10 News reported on Thursday evening that police have seen text conversations between Sara and Elovitch's wife Iris which strengthen suspicions that their husbands traded favours.

Iris Elovitch and the couple's son Or were among the seven suspects rounded up last week.

She was released from custody to house arrest Monday and son Or Elovitch was freed on bail, police said.

A statement issued after the broadcast by advisers to the premier branded the report "fake news."

"No such things ever occurred," it said in Hebrew. "Tendentious and lying leaks against Mrs. Netanyahu are intended to hurt the prime minister and the Likud government."

Hefetz is alleged to have acted as a messenger between Netanyahu and Bezeq and Walla! bosses.

He is also suspected of trying to bribe a retired judge to block a probe into the prime minister's wife over alleged misuse of public funds.

Public radio said on Friday that both were being questioned at fraud squad headquarters simultaneously with Sara but separately.

Police have now questioned the premier eight times since the beginning of 2017, and last month said there was sufficient evidence to charge him with graft, fraud and breach of trust in two other cases.

In one, he and family members are suspected of receiving one million shekels ($285,000, 230,000 euros) of luxury cigars, champagne and jewellery from wealthy figures in exchange for financial or personal favours.

In the other case, investigators suspect the premier of trying to reach an agreement with the owner of Yediot Aharonot, a top Israeli daily newspaper, for more favourable coverage.

Israeli media said police would question him on the Bezeq affair for the first time on Friday and would also take from him a statement as a witness in suspected corruption around Israel's purchase of three submarines from German industrial giant ThyssenKrupp.

The cases have fuelled speculation he could be forced to step down or call an early election but Netanyahu says he is innocent of any wrongdoing.

Eli Kamir, another former Netanyahu adviser arrested last week, was on Wednesday released from police custody but placed under house arrest.

Shlomo Filber, a Netanyahu ally for more than 20 years and former director general of the communications ministry, was freed last week after agreeing to turn state's witness in exchange for avoiding jail, police said.

He is suspected of mediating between Netanyahu and Elovitch and promoting regulatory changes worth millions to Bezeq.