Lefteris Pitarakis, Associated Press
An Israeli soldier stands next to shells for a mobile artillery unit at a position on the Israel-Gaza border, Saturday, July 12, 2014.

JERUSALEM — The Israeli military says it is ordering Palestinians living in the northern Gaza Strip to evacuate the area "for their own safety."

In a statement Saturday, the military said it would send messages to residents overnight to leave the area.

Brig. Gen. Motti Almoz, the chief military spokesman, said Israel planned to hit the area with heavy force in the next 24 hours as it steps up an offensive against Gaza militants.

Officials say the area has been used to fire rockets at Tel Aviv.