PHOTO: A large column of black smoke coming from a fully engulfed tractor on The Sweeney Farm off Hale Street could be seen across the city starting around 8 a.m. on Tuesday. Newburyport Fire Engine 5, Engine 2 and its ladder truck responded to the blaze which was extinguished before it could damage a nearby building, according to local fire officials. Fire Chief Christopher LeClaire said it appears the fire was accidental and caused by mechanical failure. There were no injuries and Hale Street remained open for the hour firefighters were on scene. The tractor and the attachment it was hauling were a total loss, LeClaire added.