Colombian presidential candidate Miguel Uribe Turbay remains in a critical condition after an assassination attempt on Saturday that recalled the political violence that roiled the nation in the 1980s and 1990s.

The 39-year-old opposition senator is out of a “neurosurgical” operation and a procedure on his left thigh, but his condition remains extremely serious, according to a statement from La Fundacion Santa Fe de Bogota, where he is being treated. It declined to give a prognosis.

Uribe’s wife had said he was “fighting for his life” following the attack, which happened while he was campaigning in a Bogota neighborhood on Saturday. In a recording Sunday, she said “he came out well from the surgery,” according to AFP. He was shot twice in the head and once in the leg.

A 15-year-old youth was arrested in relation to the shooting after being beaten up by a crowd, according to Attorney General Luz Camargo. The minor is currently receiving treatment in a medical center, she said. Authorities recovered a 9mm Glock at the scene.

Hundreds of people marched past the hospital where Uribe is being treated on Sunday to show their support for the presidential hopeful.

In a national address, President Gustavo Petro said that investigators are trying to establish who ordered the teenage gunman to attempt the hit, and don’t yet know the motive.

The candidate had visited businesses in the Modelia neighborhood, then was speaking to about 250 people when the gunfire broke out, according to local councilor Andrés Barrios, who was with Uribe at the time of the shooting.

A person from his security team threw himself on top of Uribe, Barrios said in an interview with W Radio. The senator was put into a car, then transferred to a passing ambulance, Barrios said.

The attack comes as illegal armed groups gain strength and taking more territory, emboldened by the failure of Petro’s peace plan. The gunning down of a prominent candidate — a resurgence of a type of violence that had become much less common over the last three decades — could further shake investors’ waning confidence in the Andean nation.

At the peak of Colombia’s drug cartel terror in the 1980s and early 1990s, four presidential candidates were assassinated, among other prominent Colombians. Uribe’s own mother, the journalist Diana Turbay, was murdered by Pablo Escobar’s Medellin cartel in 1991.