A loud explosion has hit a military site in the Syrian port city of Latakia, both state media and opposition sources said.

Syrian TV said a "technical error" caused the explosion on Wednesday at a military corps of engineers unit. It reported the injury of six people.

Meanwhile, the Britain-based Syrian Observatory for Human Rights said at least 13 soldiers were injured.

Opposition activists posted a video showing smoke rising, reportedly from the site of the blast.

Explosions in Latakia, part of President Bashar al-Assad's stronghold on the Mediterranean coast, have been extremely rare during Syria's two-year-old conflict.

Source: Al Jazeera and agencies