CHURCH leaders are counting the cost after their building was targeted by stone-throwing vandals for the third time in a month.

It is believed a group of children are responsible for the damage to windows at the hall behind historic Hope United Reformed Church in Trinity Street, Weymouth.

The latest attack came as members of Weymouth Operatic Society (WOS) were rehearsing for their forthcoming show, Calamity Jane.

They began their evening with a minute's silence remembering their friend Peter Cotton, who died this week, but were forced to scatter when shards of glass rained down on their heads.

Some members gave chase but the culprits fled on bikes.

It is believed the cost of the damage will run into several hundred pounds.

Geoff King, church elder and WOS chairman, said the church had no choice but to install cages to protect the 100-year-old windows and prevent further damage.

He said: "It's very sad that children would want to attack a church building.

"Not only have WOS spent a week decorating the hall but some money has been spent on refurbishing the premises recently."

Mr King said when foliage was cut near the church it exposed the building to the lane that runs towards Herbert Place. Loose stone on the wall has also provided the vandals with ready ammunition with which to take pot-shots at the windows.

He added: "The latest incident happened during a rehearsal. No-one was hurt but the glass got into people's hair and on their clothes.

"I'm sure the children responsible will not be satisfied until they've smashed the lot. That's why we have to get cages over the windows.

"It's regrettable that we have to take this action but it's the only way to protect our windows.

"They're big old windows which date back to at least 1900."

Police are investigating and would like to hear from anyone who knows who the culprits might be. A group of young children seen in Hope Square around 7.45pm on Wednesday have been linked to the vandalism.