..., who had been carried off by the guerrillas, were publicly shot this day.--(Doc. 10.) Nine Union pickets were fired upon and killed by rebel guerrillas at a point on the Mississippi opposite Helena , Ark.--A supply train of seven wagons laden with forage and commissary stores for the use of the reconnoitring force under General Stahel, was captured by a body of rebel cavalry at Haymarket, and ta...