The local commander, Gen. Paulino Coronado, says the five were killed Friday in a rural area of Tibu, a hotly contested coca-growing region near the Venezuelan border.Coronado said Saturday his troops mounted the offensive in Tibu against the Revolutionary Armed Forces of Colombia, or FARC, in February.Colombia’s military command says the FARC blew a hole in the Cano Limon oil pipeline in the area on Wednesday, spilling 4,000 barrels of crude into the Tibu River.