Jewish settlers threw stones at the cars of a delegation of American diplomats, who came to inspect suspected vandalism of nearby Palestinian-owned trees in the occupied West Bank, Israeli police said Friday.

The U.S. embassy in Tel Aviv and U.S. consulate in Jerusalem had no immediate comment on the incident, which occurred outside the Adei Ad settlement and incurred no casualties. Washington has been vocal in its disapproval of Israeli settlement policy, though such attacks against the U.S. are rare in Israel.

An Israeli police spokeswoman said the delegation arrived at Adei Ad in U.S. diplomatic cars without first having coordinated the visit with Israeli authorities. She said the purpose of the trip was to inspect nearby trees that had been uprooted in what their Palestinian owners suspect was vandalism by Jewish settlers.

"Rocks were thrown at them by residents of Adei Ad," the spokeswoman said. "We are investigating. Arrests have yet to be made." She did not know of any damage to the vehicles and had no further information on the delegates' identities.

An Adei Ad settler who was not present during the incident told Reuters that U.S. delegates came within 50 yards of the settlement in two diplomatic cars, accompanied by local Palestinians. He said someone in the delegation showed a weapon, but that report could not be confirmed.

Asked about this account, the Israeli police spokeswoman said, "We have no indication that anyone in the U.S. delegation brandished weapons."

Approximately 40 families live in the settlement. About 500,000 Israelis live in settlements among 2.5 million Palestinians in the West Bank and East Jerusalem, which Israel captured in the 1967 war and could be part of a future Palestinian state.

The settlements are considered illegal under international law. Even the United States, Israel’s staunchest backer, cites their growth among the major reasons for long-stalled Israeli-Palestinian peace talks. Israel has insisted that it would keep blocs of settlements under any Palestinian statehood deal.

Wire services