Israeli police said on Wednesday they had detained more than 30 serving and former public officials in an investigation into alleged corruption linked to a party in Prime Minister Benjamin Netanyahu's ruling coalition.

Israeli media identified the officials as being connected to Yisrael Beitenu, the party of Foreign Minister Avigdor Lieberman, and Deputy Interior Minister Faina Kirshenbaum, a senior party member, as one of the suspects.

Police spokeswoman Luba Samri said some suspects had already been brought to court for remand hearings. She said the suspected crimes in the case included fraud, breach of trust and money laundering.

Yisrael Beitenu issued a statement denying wrongdoing and said police had deliberately targeted the party ahead of a general election on March 17 in which Netanyahu is seeking a fourth term.

"We are certain of the innocence of those (suspected of wrongdoing) ... and after the noise and media fervor dissipates, it will be found that there is nothing to support these publications apart from an effort to harm (the party), and it will fail," part of the statement said.

Questioned at a public appearance hours after news of the probe broke, Lieberman said he was unaware of the investigation and declined to elaborate.

Police chief Yohanan Danino denied the investigation had been deliberately timed to be made public as elections approach.

"The investigation has been ongoing for a year and the transition to an overt probe is a result of a consideration of the evidence and the readiness to make matters public," Danino said.

Samri said the investigation "raised suspicions that the suspects collaborated ... to further their own private and public interests to procure funds ... in a manner that fundamentally damaged proper conduct".