ZAGREB, April 14 (Xinhua) -- At least three people were seriously injured Friday in an explosion at a wheat silo in Vranjic, north of Split, the second largest city of Croatia, Croatia News Agency HINA reported.

Firefighters were at the site of the explosion, putting out a fire that broke out after the explosion.

Preliminary information indicated that more people were believed to have been injured in the explosion.

The cause of the explosion has yet to be known and an investigation is under way, according to the HINA report.