UPDATE 5-Biden says Hamas must be eliminated, US officials warn war could escalate

(Adds comments from Biden in paragraph 1, 2, 4-5, 13, 16; background 6)

By Nandita Bose and Katharine Jackson

WASHINGTON, Oct 15 (Reuters) - U.S. President Joe Biden said on Sunday he believes the Hamas militant group must be eliminated but there should be a path to a Palestinian state, after top U.S. officials warned the war between Israel and Hamas could escalate.

Biden did not think American troops would be necessary on the ground as Israel has one of the "finest fighting forces," even as American warships headed to the area amid growing clashes on Israel's northern border with Lebanon.

Israel unleashed a ferocious bombing campaign over Gaza in retaliation for unprecedented attacks by Hamas eight days ago that killed some 1,300 Israelis, mostly civilians.

When asked if he believes Hamas must be eliminated entirely, Biden said "Yes, I do. But there needs to be a Palestinian authority. There needs to be a path to a Palestinian state," he said during a CBS 60 Minutes interview broadcast on Sunday.

The U.S. President warned it would be a mistake for Israel to occupy Gaza but that "taking out" Hezbollah and Hamas was a "a necessary requirement." He said "It would be a mistake to ... for Israel to occupy ... Gaza again."

Israel captured and occupied the West Bank, Gaza, and East Jerusalem in the 1967 Middle East war. It withdrew its settlers and troops from Gaza in 2005, before Hamas' takeover of the Strip in 2007.

The conflict has sent tensions soaring.

"There is a risk of an escalation of this conflict, the opening of a second front in the north and, of course, Iran's involvement," White House national security adviser Jake Sullivan told CBS earlier in the day.

Gaza authorities say more than 2,670 people have been killed there, a quarter of them children. Casualties are expected to rise as Israel prepares for a ground assault on the tiny, densely populated enclave that could start within days.

U.S. Defense Secretary Lloyd Austin announced deployment of a second aircraft carrier group late on Saturday, calling it a sign of "our resolve to deter any state or non-state actor seeking to escalate this war."

The aircraft carrier the Dwight Eisenhower will join a small fleet including the massive Gerald R. Ford aircraft carrier in the eastern Mediterranean.

"Iran is the elephant in the room," a U.S. official briefed on the situation said about the increasing military presence. "The carriers are accompanied by warships and attack planes. Every effort is being made to stop this from becoming a regional conflict."