KIEV (AFP) – One convict was killed and over 100 escaped when shelling hit a high-security prison in the besieged rebel stronghold of Donetsk in east Ukraine, local authorities said Monday.

Mortar blasts rocked the correctional facility in a western district of the city Sunday evening, hitting the living areas, administrative headquarters and an electrical substation, the city council said in a statement.

One prisoner died and fifteen more received light wounds.

Meanwhile, the bombardment also sparked a mass jail break that saw scores of detainees flee the prison.

“A riot started in the facility and 106 people escaped their place of detention,” the statement said.

By Monday morning an unspecified number had been returned to the facility and a more precise figure would be given by evening, the statement said.

An AFP correspondent reported sporadic shelling in the insurgent bastion overnight.

Shelling has pounded inner city Donetsk over the past few days as Ukrainian forces have surrounded the city and vowed to retake the pro-Russian rebel bastion.

A growing number of civilian casualties have been reported as artillery bombardments have hit hospitals and homes around the beleaguered city.

Over 1,300 have been killed and more than 285,000 people have fled their homes in the east due to fierce clashes in four months of what the Red Cross has already deemed a civil war.