RAMALLAH — At least nine people were killed in a major Israeli offensive in Jenin, Tulkarm and Tubas in the occupied West Bank, Palestinian health authorities said on Wednesday.

The Israeli military said it was preparing a statement, having earlier released the names of the five Palestinian fighters it killed on Monday in the West Bank's Nur Shams refugee camp.

Clashes in the West Bank have risen sharply since the start of the Israel-Hamas war in Gaza. Israel has stepped up operations against armed militant groups in the territory, while Jewish settlers have also launched frequent vigilante-style attacks on Palestinian communities.

READ MORE: Palestine rejects Israel's further settlement in West Bank

The armed wings of Hamas, Islamic Jihad and Fatah said in separate statements their gunmen were detonating bombs against Israeli military vehicles as they fight Israeli forces in the three West Bank areas.

Islamic Jihad said Israel was trying to expand the conflict from Gaza to the West Bank, adding its fighters were using machineguns in close range combat with Israeli troops and targeting military bulldozers with explosives.

Reuters was able to verify CCTV footage that showed Israeli military vehicles moving down a street in Jenin on Wednesday.

Thousands of Palestinians have been arrested in raids and more than 660 - fighters and civilians - have been killed in the West Bank and East Jerusalem since the war in Gaza began nearly 11 months ago, according to Palestinian Health Ministry figures.

At least 30 Israelis have been killed in attacks in Jerusalem and the West Bank during the period, according to Israeli tallies.

The latest round of Israeli-Palestinian violence began on Oct 7 after Hamas militants stormed into southern Israel, killing 1,200 and taking more than 250 hostages, according to Israeli figures.

READ MORE: 14 Palestinians killed in Israeli operation in West Bank

Israel's Gaza campaign has since levelled swathes of the enclave, displaced nearly all its 2.3 million people multiple times, given rise to deadly hunger and disease and killed more than 40,400 people, Palestinian health officials say.

Internationally mediated talks to end the conflict continue, with Hamas and Israel trading blame for a lack of progress, and the United States expressing optimism that a ceasefire can be reached.