Eleven soldiers have been killed in an explosion at a Syrian army site in the eastern province of Deir Az Zor, the country's Ministry of Defence announced.

The blast struck a weapons cache within a Syrian Arab Army position in the town of Ayyash, in western Deir Az Zor, according to the official SANA news agency, citing the defence ministry. Nine other soldiers were wounded, the provincial government said in a statement.

The cause of the explosion has not been determined. An investigation is under way, the statement added.

Syria's military held a funeral procession for the soldiers on Saturday, a day after they were killed. Videos broadcast on state television showed mourners gathered outside the National Hospital in Deir Az Zor city, where the bodies, wrapped in Syrian flags, were carried in the procession. State media reported that the soldiers were killed while transporting heavy ammunition at the site.

The Deir Az Zor blast was the second explosion at a Syrian military site in less than two weeks.

On September 9, an explosion struck a temporary weapons and war-remnants depot in Sarmada, in the northwestern province of Idlib. The Syrian Defence Ministry said that blast killed 14 soldiers and wounded more than 10 people, including some civilians. The ministry said it took responsibility for the incident and that the depot had been used to collect weapons and munitions left over from Syria's civil war, ahead of their transfer under standard procedures.

Syria's emergency management minister, Raed al-Saleh, said at the time that his ministry was working with other government bodies to keep such sites clear of civilians. He acknowledged, however, that some locations are difficult to fully secure because civilians are involved in collecting abandoned munitions.

Earlier, on September 1, a vehicle carrying ammunition exploded in Binnish, also in Idlib province, killing five people and wounding others, according to Syrian state media.

Explosions of this kind have become frequent in Syria as the country works to clear vast stockpiles of weapons and munitions left behind after more than a decade of civil war.