An American man has been arrested in Israel on suspicion of "the deliberate defacement" of valuable sculptures at the Israel Museum in Jerusalem, Israeli police have confirmed.

The unnamed 40-year-old was arrested after police were called to reports from security personnel at the cultural institution in Jerusalem.

According to the Jerusalem Post, two ancient Roman sculptures dating to the 2nd century CE were damaged.

In a statement sent to CNN, Israeli police said: "Yesterday (Thursday) in the late afternoon, Jerusalem District Police received a report from security personnel at the Israel Museum about a visitor who intentionally destroyed sculptures of significant financial value displayed at the museum, causing substantial damage."

The suspect, an American citizen, was taken in for questioning at the Moriah station in the Israeli capital, police said.

The police statement continued: "During the initial investigation, it was revealed that the suspect carried out the act because he considered these sculptures to be 'idolatrous' and contrary to the Torah."

But the man's lawyer denied that he had been acting on fundamentalist religious belief, saying instead that he was suffering from mental illness.

The suspect appeared in court on Friday where magistrates extended his detention until Monday while the police investigation continues.

The man's lawyer, Nick Kaufman, requested that his client's name not be disclosed. The magistrate rejected this request but postponed the decision on whether to name him until Sunday morning.

In an email sent to CNN, Kaufman said: "The suspect did not act out of iconoclastic fanaticism. His acts prior to the incident and general demeanor suggest that he is suffering from a well recognized condition known as the Jerusalem Syndrome.

"With his agreement and that of the police, he was referred for psychiatric evaluation with the expectation that he will be released from pre-trial detention on Monday."

Jerusalem syndrome is a rare condition in which tourists become so overwhelmed by the city's history and power that they dissociate from reality and believe themselves to be biblical figures.

The incident comes during the week-long festival of Sukkot and just days after Israeli police arrested five people on suspicion of spitting in the vicinity of Christians or churches in the Old City of Jerusalem.