Joma'a al-Saqqa, chief of emergency at the Shiffa Hospital in Gaza City, said that two bodies of men and a third in critical conditions were sent to the hospital after they were shot.

Witnesses in the Beach refugee camp in western Gaza said that firefight erupted in the camp between members of the Hamas-dominant auxiliary force led by the interior ministry and militants from Fatah movement led by Palestinian President Mahmoud Abbas.

The clash took place as the Hamas-led forces, who withdrew from the camp on Thursday after a Fatah militant in the camp was shot dead, returned back to camp.

Relatives and friends of the killed Fatah militant protested the return of the Hamas force and quarreled with Hamas members, said the witnesses, adding that both exchanged fire following arguments between the two sides.

The fierce armed clashes erupted in narrow streets of the refugee camps, where two people were killed by the gunfire of the Hamas-led auxiliary force.

Meanwhile, a 24-year-old pregnant woman was killed in southern Gaza Strip and her husband, who is a senior member in the Hamas' armed wing Izedein al-Qassam, was seriously wounded after their car was shattered by a group of gunmen with automatic machine-guns.

Local witnesses said that the car carrying Yasser al-Ghalban, his wife Reem and his brother Mohamed were driving south of the Gaza Strip town of Khan Younis when it was attacked. Since the start of the clashes between Hamas and Fatah militants about one and a half months ago, at least ten Palestinians and one Jordanian have reportedly been killed in the Gaza Strip.

Tension is growing in the strip after Hamas movement accused President Abbas of trying to topple the national dialogue by imposing advance conditions on Hamas.

At the opening session of national dialogue held on May 25, Abbas said that he would order a referendum within 40 days if the inter-Palestinian dialogue fails to adopt the National Accordance filed by Palestinian prisoners in Israeli jails.