Israeli forces clashed with members of the militant Islamic Jihad in the Gaza Strip on Wednesday, killing one gunman and wounding another in a rare cross-border incursion, witnesses and hospital officials said.

An Israeli military spokeswoman said the air force had struck two groups of gunmen preparing to launch rockets.

But she had no immediate comment on a ground operation, in which Hamas said a small number of armoured vehicles crossed about 150 m (yards) beyond the border, east of Gaza City.

Hamas also dispatched fighters to the area.

Islamic Jihad at times is allied with Gaza's Hamas rulers but the group has chafed at recent efforts by the more powerful faction to impose de facto truces across the coastal territory.

Hamas and Israel carried out an Egyptian- and German-brokered prisoner swap in mid-October that stirred expectations of a possible broader accommodation, although the governing Islamist movement spurns permanent peace with the Jewish state.

Fighting between Israeli forces and Islamic Jihad later that month killed nine gunmen from the group and an Israeli civilian who was hit by a cross-border Palestinian rocket salvo.