DUBAI/JERUSALEM (Reuters) -Explosions echoed over an Iranian city on Friday in what sources said was an Israeli attack, but Tehran played down the incident and indicated it had no plans for retaliation - a response that appeared gauged towards averting region-wide war. Iran's foreign minister said the drones, which the sources said Israel launched against the city of Isfahan, were "mini-drones" and that they had caused no damage or casualties. The limited scale of the attack and Iran's muted response appeared to signal a successful effort by diplomats who have been working to avert all-out war since an Iranian drone and missile attack on Israel on Saturday.