Syria's state news agency and opposition activists say shelling in and around the capital has killed at least 18 people.

Syria's state-run SANA news agency says two shells struck Arnous Park in Damascus late Tuesday as many people were out shopping ahead of the Muslim holy month of Ramadan, expected to begin Thursday. It says the shells killed nine people and wounded 13.

The shelling came after government forces fired rockets into the rebel-held Damascus suburb of Douma.

The Britain-based Syrian Observatory for Human Rights said Wednesday that the government fired Iranian-made "elephant" rockets on Douma, killing nine people, including two children and six women.

Government forces and opposition fighters have exchanged shelling the past.

Airstrikes, artillery and rockets have destroyed wide areas of the Damascus suburbs in recent months.