A Syrian monitoring group and paramedics say government shelling and airstrikes on rebel-held suburbs of the capital, Damascus, killed at least 98 people on Monday.

The Britain-based Syrian Observatory for Human Rights says it was the deadliest day in three years in the area known as Eastern Ghouta.

The Syrian Civil Defense, also known as White Helmets, said the shelling and airstrikes killed 98 and that some people are still under the rubble.

The Observatory says 20 children and 15 women were among those killed on Monday.

The targeted suburbs have been subjected to weeks-long bombardment that has killed and wounded hundreds of people.

Opposition activists say government forces have brought in reinforcements in preparation for a wider offensive on the area — the last main rebel stronghold near Damascus.