The United States appealed for Israeli restraint Friday as casualties mounted from its military drive into Gaza, aimed at retrieving a kidnapped soldier and quelling Palestinian rocket fire. U.S. diplomats are in contact with the two parties and other governments in the region.

An Israeli soldier exits an armored personnel carrier during a military operation in the Gaza Strip

Officials here stress that it was the military wing of Hamas that touched off the crisis with its role in the tunnel attack into Israel and kidnapping of the Israeli soldier June 25.

But they're expressing growing unease about the casualties and political fall-out from the ensuing Israeli military campaign, and urging Israel to ensure that innocent Palestinian civilians are not hurt.

A State Department spokeswoman, Julie Reside, expressed concern about reports that civilians may have been among those killed in an Israeli air strike and tank fire against Palestinian fighters Friday in the northern Gaza strip.

She said Hamas militants precipitated the crisis, and their refusal to release their Israeli hostage continues to place innocent Palestinians in harm's way.

She said there is no question that Israel has a right to defend itself, but also said the United States urges the Israeli government to ensure that innocent civilians are not harmed, to exercise restraint, and to refrain from adversely affecting the Palestinian humanitarian situation.

European comments on Israeli actions have been more pointed. A statement Friday by Finland, which holds the European Union rotating presidency, said the EU condemns the loss of life from what was termed a disproportionate use of force by Israel.

Spokeswoman Reside said senior Bush administration officials are monitoring the situation, and remain in touch with the Israeli government and Palestinian Authority chief Mahmoud Abbas.

The United States has no contacts with the Hamas-led Palestinian government because of its refusal to renounce violence and accept Israel's right to exist.

Reside said U.S. officials are also in contact with governments in the region, including Egypt and Turkey, which she said have been particularly helpful.

Secretary of State Condoleezza Rice met Wednesday with Turkish Foreign Minister Abdullah Gul, and thanked his government for interceding with Syria to try to get Damascus to use its leverage to win the release of the kidnapped Israeli.

The military wing of Hamas, whose leader Khaled Mashaal is based in Damascus, has acknowledged its members were among the gunmen who tunneled into Israel two weeks ago, killing two Israeli soldiers and taking a wounded third soldier, Corporal Gilad Shalit, back into Gaza.

It was the first breach of the Israeli border since Israel withdrew from Gaza in September, though tensions had been high before the incident because of rocket firings into Israel, which have continued in recent days.

Secretary Rice said Wednesday the United States wants pressure on Hamas to stop the rocket attacks, and is trying to ease the suffering of Palestinian civilians by among other things working to keep Gaza crossing points open for the movement of humanitarian aid.