The Israeli artillery targeted a location east of Beit Lahya and another east of Beit Hanoun, injuring three farmers who were working in their lands near the border fence.
The three were taken to a hospital in Beit Hanoun for treatment.
Israel claims shot were fired from Gaza at Israelis who were working on the border fence, lightly injuring one and prompting its retaliatory attack.
The abrupt escalation came a day after Palestinian President Mahmoud Abbas travelled met Defense Minister Benny Gantz at his home, in a move condemned by Hamas.
