NEWS BRIEF The war lasted nearly 60 years and killed a quarter-of-a million people. Thousands were kidnapped, and more were injured by landmines placed in the jungles controlled by the Revolutionary Armed Forces of Colombia (FARC). On Monday, the Marxist group’s rebel leader, Timochenko, used a pen made from a bullet to sign a peace deal with Colombia’s president, Juan Manuel Santos, which ends the last big Cold War-era conflict in Latin America.

The deal, signed in Cartagena, marks the end of four years of negotiations between the government and the rebels. Colombians will vote October 2 on whether to accept the deal—and it’s predicted they will—which would draw FARC soldiers out of the jungle and into designated disarmament zones set up by the United Nations. They will then form a political party recognized by the government and be given 10 seats in Colombia’s 268-member Congress. As part of the deal, FARC was removed from the European Union’s list of terrorist organizations.

Before the signing, Santos had elaborated on the significance of the pens by saying, “We are going to sign with a bullet-pen ... to illustrate the transition of bullets into education and future.”

To signify peace, some of the 2,500 foreign dignitaries and FARC guerrillas who attended the ceremony dressed in white. Here’s a photo of what that looked like:

Many FARC leaders voted Friday to approve the deal, which was just as significant as the signing itself. There was worry some rebel blocs would refuse the terms, but after FARC representatives deliberated for a week in the jungle, one leader by the name of Ivan Marquez declared the war over, saying, “Tell Mauricio Babilonia that he can let loose the yellow butterflies,” referring to a character in Gabriel Garcia Marqeuz’s 100 Years of Solitude.

But the deal was not without its critics.

Some Colombians say they believe FARC should be held more accountable for the many deaths and kidnappings that resulted from their war, started in 1964. One critic is former President Alvaro Uribe, who believes some FARC leaders should serve jail time. Instead of criminal courts, the peace deal establishes special tribunals to hear cases, but allows rebels who admit wrongdoing to receive lesser sentences that include “restorative” justice for the victims and their families.

FARC rebels have 180 days now to disarm. About 7,500 fighters are expected to leave the jungle and return to regular life, and this will not be easy.

One of the major questions that remains is who will fill FARC’s void. The group controlled 170,000 acres of coca plants, a crop that makes up much of the world’s cocaine. Part of the government’s responsibilities in the deal will include weaning poor farmers from the coca onto other lucrative crops. There are also several other militant groups fighting for control of Colombia’s jungle, including another Marxist guerrilla movement, the National Liberation Army.

But firstly, and most importantly, Colombia must make sure the peace deal sticks.