bogota colombia send letter venezuelan foreign ministry tuesday protest incursion military helicopter troop nation border late series similar incidents draw criticism colombia incident occur nov. 15 16 near town tibu norte de santander province colombia foreign ministry say statement events already protest foreign ministry meet arrange foreign minister analyze happen request measure take prevent recurrence say foray venezuelan troop colombia increase recent years heighten diplomatic tension government colombia president juan manuel santos venezuelan president nicolas maduro santos accuse maduro destroy democracy venezuela maduro say colombia part international conspiracy seek overthrow government colombia venezuela share border 2,219 km 1,379 miles contraband illegal drug frequently pass accord security source colombia protest venezuelan military cross border