A United Nations agency called on Israel on Sunday to investigate the death of a Palestinian teacher employed by the agency who was killed in her home during an Israeli raid last week in the Gaza Strip.

"We're calling on the Israelis for an impartial investigation," said Christopher Gunness, spokesman for the U.N. Relief and Works Agency (UNRWA), for which Wafa al-Daghma worked as a teacher at an elementary school for refugee children.

"We want to see accountability."

A spokesman for the Israel Defense Forces said they were looking into the matter. Dozens of civilians have been killed in Gaza this year in air and ground attacks that Israel says are directed against militants who fire rockets into its territory.

Immediately after the violence near Khan Yunis in the south of the Gaza Strip on Wednesday, the army said troops attacked militants. Islamic Jihad said one of its fighters was killed and six were wounded in an Israeli air strike in the area.

Palestinian medics and relatives at Abassan, a village east of Khan Younis, said Daghma, 32, was at home with three of her children when IDF troops with tanks approached.

Gunness said inquiries by UNRWA suggested Daghma was killed when troops blasted open the door of her home in order to take the building as an observation post.

Daghma's 13-year-old daughter Samira told reporters last week that her mother had ordered her and a sister and brother aged under 5, into another room. The children then heard an explosion, she said. Soldiers then entered the house.

Only some hours later, when the soldiers left, were the children able to leave the room where they had been held and neighbours and relatives were able to retrieve Daghma's body.

Human rights groups have called on Israel to mount independent investigations into several civilian deaths in the Gaza Strip recently. Among these was the killing of a mother and four of her children on April 28 and the killing of a Reuters television cameraman and several other civilians on April 16.

After the deaths of Myassar Abu Meateq and her family as they ate breakfast in Beit Hanoun two weeks ago, the IDF released video footage that it said indicated their home was damaged by explosives carried by a militant who was hit and killed by Israeli fire as he passed the house.

Israeli human rights group B'Tselem has challenged the army's account of this "secondary explosion" and said witness testimony and other evidence suggested the family was killed by the gate of their home being blown off by an Israeli missile.

B'Tselem called for a full military police investigation.

Reuters is awaiting results of a promised army inquiry into the killing of its journalist, Fadel Shana, by a tank that fired a controversial shell loaded with darts while he was filming.