Tel Aviv  - The Israeli Army has launched "roof knocking" operations by which the occupants of the buildings in Gaza they about to bomb are warned beforehand, Israeli media reports said Friday.

Warnings, issued by telephone, voicemail or SMS, were intended as a means of limiting civilian casualties in the conflict, the Haaretz newspaper said. Civilians were given
10 minutes to leave the premises.

An Israeli Army spokesman declined to confirm the reports or respond to questions about such tactics being used in its ongoing confrontation with Palestinian militants.

"In some cases advance warnings are given to reduce the number of victims," he said.

The Israeli Army apparently used "roof knocking" in its killing of senior Hamas official Nizar Rayan on Thursday, Haaretz reported. His family had received warning that the building was about to be attacked, but they had decided to remain inside, the newspaper said. (dpa)