The attacks on the two high-rise buildings damaged offices of the Hamas TV station, Al Aqsa, and a Lebanese-based broadcaster, Al Quds TV, seen as sympathetic to the Islamists. Germany's public broadcaster ARD; Russia Today, a state TV network that broadcasts in English; and Sky News Arabia said they lost equipment in the attacks.
A Gaza press association said six Palestinian journalists were wounded, including one who lost a leg.
Christophe Deloire, the director of Reporters Without Borders' international headquarters in Paris, called the attacks unjustified and a threat to freedom of information. He demanded an investigation into the circumstances of the raid.
"Even though the outlets targeted are linked to Hamas, it does not legitimize the attacks," he said. "Attacks against civilian targets constitute war crimes."
The Israeli military said the strikes targeted Hamas communications equipment on the buildings' rooftops and accused the group of using journalists as "human shields."
Lt. Col. Avital Leibovich, an Israeli military spokeswoman, urged journalists to stay clear of Hamas bases and facilities.
In Moscow, Russia Today, a state TV network that broadcasts in English, reported that the office of its Arabic-language channel, Rusiya Al-Yaum, was heavily damaged in the strike but none of the crew was injured.
"Fortunately for them, they had left the Shawa building about an hour before the Israeli planes delivered the strike. RT's office was damaged, so the crew will move to a less-affected floor of the center."
Germany's public broadcaster ARD said its Gaza office was hit.
"Thanks God, nobody was injured," said correspondent Markus Rosch in a blog entry on the broadcaster's website. "At night, I went to bed hoping for a ceasefire. But in the morning it went off again on both sides. Our ARD office in Gaza was also hit."
Sky News Arabia issued a statement condemning the attacks and saying they caused extensive damage to its property and "considerable and unacceptable distress to our staff." Sky News Arabia is a joint venture between BSkyB in Britain and the Abu Dhabi Investment Corp, based in Abu Dhabi.
The statement claimed the Israeli attacks "targeted journalists covering the current military operations in Gaza" and demanded "that Israeli authorities respect and abide by the international conventions not to target media and to ensure the safety of journalists covering conflict zones."
(Copyright 2012 by The Associated Press. All Rights Reserved.)