Colombia's ELN rebels are responsible for three bomb attacks against police stations that killed seven and wounded dozens more over the weekend, the nation's defense minister said on Monday, as the government weighs the future of peace talks with the group.

Five police officers were killed and more than 40 wounded in a bombing in the port city of Barranquilla on Saturday morning.

Two more officers died, and one was wounded just before midnight on Saturday in the rural Bolivar province, and the third attack took place about four hours later in the city of Soledad, injuring five police and one civilian.

"The authorship of these terrible actions is on the head of the National Liberation Army," Defense Minister Luis Carlos Villegas told local Caracol Radio, adding that the violence raised the question of whether the group wants peace.

Read more: U.S. News & World Report