MEDELLIN -- Four farmworkers were killed by right-wing paramilitaries Monday at
 an improvised roadblock in northwest Colombia, local officials reported.

 Two of the laborers were traveling on a bus and two others on a truck when their
 vehicles were stopped near the town of Betulia, 64 miles southwest of Medellin.

 Officials said that, in each case, the victims were forced from their vehicles and
 shot to death.