The Israeli military makes extensive use of drones in combat situations
Israeli drones unlawfully killed at least 29 Palestinian civilians during the Gaza conflict six months ago, the rights group Human Rights Watch says.
It cited six attacks in which operators of pilotless aircraft allegedly failed to verify if targets were combatants as required by the laws of war.
In three of the alleged cases, the group said the unmanned aircraft had fired on children playing on rooftops.
Israel said all its actions and arms conformed with international law.
Israel has a fleet of US and domestically manufactured drones but will neither confirm nor deny that they carry weapons.
The 39-page report focuses on six alleged strikes, based on interviews with victims and witnesses, investigations of the attack sites, Israeli military and media reports on the fighting.
It says that other human rights groups have documented many more casualties from similar attacks.
Drone-launched missiles are considered among the most precise weapons in the world, the report says.
But they can only be as good at sparing civilians as the people operating them, it adds, and Israel's targeting choices led to loss of civilian lives.
"Drone operators can clearly see their targets on the ground and also divert their missiles after launch," said Marc Garlasco, senior military analyst at Human Rights Watch and co-author of the report.
"Given these capabilities, Israel needs to explain why these civilian deaths took place."
But the Israeli military says it only acted against military targets during the conflict and that HRW has been taken in by propaganda from the Islamist movement Hamas, which runs the Gaza Strip.
More than 1,000 Palestinians are known to have died in the December-January Israeli operation in Gaza.
Thirteen Israelis also died in the conflict, including in so-called friendly fire and Palestinian rocket attacks.