"We took over the Hamas television to broadcast warnings," a military spokeswoman said, indicating the takeover would probably last for a number of hours. But AFP correspondents in Gaza said they could see no warning being sent out by the army.
On Sunday, the army took over Hamas radio broadcasts in Gaza for several hours.
Also on Sunday, at least eight journalists were injured when Israeli jets bombarded two media buildings in Gaza City, with the military saying it had hit Hamas communications sites.
A statement from the Israeli army after the attack called on "international journalists... to stay clear of Hamas's bases and facilities, which serve them in their activity against the citizens of Israel."
Since violence erupted on Wednesday, 90 Palestinians have been killed in Israeli strikes on Gaza. Over 500 rockets hit Israel, resulting in three deaths.