It was not immediately clear who carried out the raids, which hit a market and several neighbourhoods across the city.
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The Syrian Observatory for Human Rights said the dead included 13 women and 13 children, but it was not immediately clear how many civilians were among the remaining victims.
The monitor said dozens more were wounded in the strikes, warning that the death toll could rise even further.
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It could not identify who carried out the strikes, but the Syrian government and its ally Russia have regularly conducted raids in Idlib province.
"People were shopping before the (Muslim feast of) Eid al-Adha next week, which is why the toll is so high," said Observatory head Rami Abdel Rahman.
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