RAMALLAH, Nov 19 (Reuters) - Vandals set fire to the entrance of a West Bank mosque on Monday, damaging the door, in an attack that villagers blamed on Jewish settlers.

Residents of the Palestinian village of Orif, near the city of Nablus, said a group of settlers from a nearby settlement came to the mosque before dawn, poured gasoline on an old carpet near the mosque's door, and set it ablaze.

"The settlers tried to break into the mosque, but it was locked," Orif resident Issam al-Safadi told Reuters.

"So they settled with burning the old carpet and the door."

The Israeli army said it was called to the scene and is investigating the incident.

Israeli rights group B'tselem says vigilante settler groups are suspected of vandalising at least 10 mosques in the Israeli-occupied West Bank since 2009.

About 500,000 Israelis and 2.5 million Palestinians live in the West Bank and East Jerusalem, areas which, along with the Gaza Strip, were captured by Israel in the 1967 Middle East war and which Palestinians claim as their own for a future state.

Most world powers deem the Jewish settlements illegal, something Israel disputes.

The mosque vandalism occurred on the sixth day of a conflict in Gaza Strip, with Israeli forces bombarding the enclave and Palestinians firing hundreds of rockets into southern Israel. (Writing by Jihan Abdalla)