Big explosion heard in Aden, Yemen

On Thursday evening a loud explosion was heard in the Yemeni city of Aden residents and a security
The explosion took place just outside a central prison in the southern port city, they added.
The security source said the explosion happened in an empty area and damaged a wall.
There were no immediate reports of deaths or injuries.
Pictures posted on social media showed a plume of smoke that appeared to rise from an area outside the prison.