The US Bureau of Alcohol, Tobacco, Firearms and Explosives is offering a $5,000 reward for information leading to the arrest and conviction of the burglars who stole at least $100,000 worth firearms early Sunday from Ackley and Son Sporting Goods in Westfield. Authorities say that the thieves climbed a utility pole to cut a phone line tied to the store’s burglary alarm system, rendering it useless. An estimated 100 to 200 pistols, rifles and civilian assault weapons were taken along with cash and ammunition. The serial numbers of all the guns were recorded.