HALIFAX -- Police are asking for the public's help as they investigate fires set earlier this year at a Halifax church.

Investigators say two separate arsons occurred at St. Andrews United Church on Coburg Road in May and in July.

In the May incident, police say someone entered the church and set a number of fires outside the administrative offices on the main floor.

In July, fires were set on the basement floor and the main floor of the church, targeting administrative offices, the childcare office and the main sanctuary.

Police say a witness observed a woman leaving the church moments before the blaze.

The estimated cost of the damage caused by the fires is over $700,000.