Foreign Minister Tzipi Livni said on Wednesday that Israel could not put up with "flagrant violations" of the cease-fire agreement with Hamas in the Gaza Strip, after dozens of Qassam rockets hit Israel on Wednesday.

The rocket barrage came a day after an Israel Air Force strike in the southern Strip killed at least five militants and wounded several others.

Hamas claimed responsibility for the rockets, but vowed interest in maintaining the five-month old truce.

Defense Minister Ehud Barak said that "Israel is committed to the cease-fire agreement," but will continue to do whatever it can to foil attacks against Israeli soldiers and civilians.

After praising the Israel Defense Forces troops for thwarting an imminent attack, Barak said that "we are all taking advantage of the relative quiet to bring back [the abducted IDF soldier] Gilad Shalit."

The group blamed Israel for operating in Gaza with the intention of thwarting Palestinian reconciliation efforts, and said it had asked Egypt to help return calm to Gaza's border with Israel.

None of the rockets fire on Wednesday caused any damages or injuries. Two of the rockets exploded in the northern Negev city of Ashkelon, one struck a kibbutz in the western Negev and six others were located in open fields.

Also on Tuesday, IDF soldiers killed a Hamas gunman and wounded two others on Tuesday in the first armed clash in the Gaza Strip since a cease-fire was declared in the territory in June, Palestinian medics said.

An Israeli army spokeswoman said troops had entered the territory to destroy a tunnel which Gaza militants had dug under the border to try to abduct soldiers.

According to Palestinian sources, the troops entered the area east of Deir el-Balah and carried out an operation at a house belonging to the Abu Hamam family.

An exchange of fire took place between the troops and Hamas gunmen. Four IDF soldiers were wounded during the operation, two of them moderately. The others were lightly injured.

Six mortar shells were also reportedly fired at Israel from Gaza on Tuesday.

"Qassam fighters are engaging in violent armed clashes with a Zionist (Israeli) force that raided east of central Gaza Strip," Hamas said in a statement on Tuesday.

Abu Obeida, a spokesman for Hamas' military wing, said in a text message to reporters that Hamas troops were engaged in a gunfight with Israeli forces in central Gaza.

Hamas quickly vowed revenge for its losses.

"Our response will be harsh, and the enemy will play a heavy price," Hamas said in a statement on its military wing's Web site.

Palestinian residents in the area of the al-Bureij refugee camp in the central Gaza Strip reported seeing Israeli soldiers about 300 meters inside Gaza.

They also reported hearing shots fired from Israeli military vehicles positioned on the Israeli side of the border fence and the buzz of unmanned drones overhead.

The residents said Hamas gunmen had responded by firing at the troops. Residents said that one of the Israeli drones fired a missile into the area where the firing had occurred.

Palestinian medical workers said three gunmen were wounded by shrapnel from the Israeli missile.

An Egypt-brokered cease-fire agreement between Israel and the Gaza Strip was signed earlier this year, and went into effect on June 19.

The IDF argued that the raid did not constitute a violation of the cease fire, but instead was a legitimate step to remove an immediate threat to Israel from Gaza, which is controlled by the Islamic militant group Hamas.

Gaza militants have occasionally launched makeshift rockets into southern Israel in violation of the ceasefire and this has prompted Israel to temporarily close its borders with Gaza in response.

Hamas had agreed to halt rocket attacks in return for the gradual lifting of a blockade Israel imposed on the Gaza Strip two years ago.