Istanbul, Turkey (CNN) -- One day after Syrian rebels accused government forces of a deadly bombing near a hospital in the besieged city of Aleppo, opposition groups said another 151 people had been killed in the fighting Thursday. The majority of those deaths occurred in the Syrian capital of Damascus and its suburbs, according to the Syrian Observatory for Human Rights, a London-based opposition group. Another 34 were killed in Aleppo, where some of the heaviest fighting has occurred. The 20-month civil war has claimed more than 42,000 lives, according to the latest tally from the opposition Center for Documentation of Violations in Syria. The group counts 3,133 government soldiers among the dead.
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NEW: By Thursday, another 76 people had been killed in the fighting, opposition groups say
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Rebels say a Syrian airstrike hits near Aleppo hospital
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Turkey requests Patriot missiles amid concern over "threats and risks" from Syrian crisis
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NATO says the missiles would demonstrate solidarity in the alliance
Turkey has been careful to make clear it plans no offensive action and does not want a war with @placeholder, which shares a more than 500-mile border.