Syrian war planes attacked towns in the country’s north and east and killed at least five civilians in a strike on an olive oil press as fighting raged in the capital Damascus yesterday, opposition activists have said.

Rebels battled Government forces in the Damascus suburb of Kfar Souseh, on the edge of the centre of the capital, said the Syrian Observatory for Human Rights, a British-based monitoring group.

The latest fighting followed recent battlefield gains by the rebels in their struggle to topple President Bashar al-Assad, although it was far from clear if a strategic breakthrough was likely any time soon.

Syrian state television said that two people were killed and four wounded in a “terrorist suicide car bomb” in Artouz, near Damascus.

The Observatory said the explosion was caused by a car bomb next to a military police checkpoint.

Near the Old City, a second car bomb killed one person and blew the legs off another man, according to opposition activist Samir al-Shami. He said it was unclear if the car, a white Toyota, was rigged by Assad loyalists or rebels.

The rebels also shot down a military helicopter on Tuesday, according to video footage posted on You Tube.

The Local Coordinating Committee opposition group said the Free Syrian Army had downed a helicopter near the Sheikh Suleiman army base, 30 kilometres northwest of the contested city of Aleppo.

Combat also took place in the Baba Amr district of Homs city, an area that was overrun by Government troops in February, as well as in Aleppo, Deir al-Zor, Deraa, Idlib province and Hama province, the Observatory said.

A Government jet dropped barrel bombs – cylinders full of explosives and petrol – at the Abu Hilal olive oil press, two kilometres west of Idlib city, activist Tareq Abdelhaq said.

At least five people died and five were wounded in the attack, the Observatory said. Abdelhaq said at least 20 died and 50 hurt.

The victims were civilians waiting to press their olives for oil, according to activists.

An estimated 40,000 people have been killed in Syria since March 2011 when protests inspired by the Arab Spring broke out against Assad, whose family has ruled autocratically for four decades. Assad has relied on fighter jets, helicopters and artillery to subdue the revolt, which started peacefully.

Rebels have captured at least five army and air force installations in the past 10 days, putting pressure on Assad’s forces in Aleppo and Idlib and the eastern oil region of Deir al-Zor.

The Opposition wants international military aid, particularly against air attacks, but Western powers supporting the uprising are wary of radical rebel Islamist units.