Israeli aircraft launched seven sorties overnight, striking buildings and posts operated by Islamist movement Hamas, the senior coalition partner in the Palestinian government, whose fighters have fired rockets at Israel.

Local medical sources cited five people wounded in strikes that Palestinians said hit a small guardhouse near the home of prime minister Ismail Haniya in the Shati refugee camp, but the military denied his house had been the target.

Three days ago, Israel warned Hamas, of which Haniya is a prominent member, that none of its leaders was immune from attack after a rocket fired by its militants killed an Israeli woman.

Other targets included buildings operated by Hamas's controversial paramilitary Executive Force, a money-changing office and a weapons workshop.

The military said it attacked two Hamas posts in Gaza City and the southern town of Khan Yunis, three buildings operated by Hamas in the northern Gaza Strip and a business "involved in transferring funds to terror organisations".

A "weapons-manufacturing facility" used by Hamas's smaller rival Islamic Jihad, which has claimed most of the attacks on Israel in the past two years, was also attacked in Rafah in the southern Gaza Strip, the military said.

It accused Palestinians of trying to fire 19 makeshift rockets in the past 24 hours, eight of which hit Israel, and added that two mortar shells caused damage near the Erez crossing terminal separating the Jewish state from Gaza.

An army spokeswoman said fighters fired five rockets from Gaza into Israel's Negev desert on Friday, causing no damage or casualties.

The violence came one day after the beleaguered Abbas urged Palestinian fighters in Gaza to hold their fire and called for a truce with Israel.

"We don't need these futile firings of rockets and they have to cease so that we can reach a reciprocal truce with the Israelis in the Gaza Strip and the West Bank," he said after meeting EU foreign policy chief Javier Solana.

A six-month ceasefire has collapsed amid a sharp increase in rocket attacks and air strikes, which Israel resumed on May 16 in response.

Air raids have killed 13 Palestinian civilians and 25 militants, but have failed to halt the rocket bombardment, with more than 130 slamming into Israel over the past week and a half, killing the woman and wounding 16 other people.

Overnight Wednesday to Thursday, Israeli soldiers took the campaign against Hamas to the West Bank by detaining 33 senior party members, including a cabinet minister and three members of parliament.

Israel seized the 33 Hamas officials in raids centred on Nablus. Those held included education minister Nassereddin al-Shaer, who was detained in a previous clampdown last year, three lawmakers and at least seven mayors.

The United States has voiced concern, with State Department spokesman Tom Casey saying the detentions "raise particular concerns."

"Certainly Hamas is a foreign terrorist organisation engaged in terrorist attacks against Israel. But we have previously noted when these kinds of issues came up before, that the detention of elected members of the Palestinian government and legislature does raise particular concerns," Casey said.

The bloodshed in Gaza over nearly two weeks was sparked by a renewed bout of clashes between Hamas and Abbas's Fatah, caused widespread international concern and undercut hopes of reviving peace efforts.