Four Spanish soldiers were injured when a mortar shell exploded close to them as they were participating in a military exercise close to Zaragoza in central Spain on Friday.

Regional television network Aragon Television reported the four suffered the injuries early on Friday morning when the shell exploded just as it was being fired out of the mortar at the San Gregorio training ground.

The four suffered light injuries and were taken to the Zaragoza Military Hospital for treatment.

Local media also reported that this was the fifth accident at San Gregorio in the last six years.

The most recent accidents happened during a NATO training exercise held in San Gregorio on Nov. 4, 2015, when three Belgian troops were injured when a truck overturned, two days before a further 14 people suffered injuries following an accident involving a Czech helicopter.

The year 2014 saw the death of a parachutist during a night exercise, while in 2011 a sergeant died in another incident involving a mortar bomb.

source: Xinhua