Bolivian police arrested Sunday the man long wanted over the murder of a prominent Bolivian socialist leader, 35 years after the dictatorship-era killing, President Evo Morales said.

Former soldier Froilan Molina, alias "Killer," allegedly murdered Marcelo Quiroga Santa Cruz and had been on the run since he was sentenced to 30 years in prison in the early 1990s.

Molina was arrested during a raid on a house in La Paz involving 80 police officers, the president told a press conference. 

He had been in hiding for three decades and was sheltering in a bedroom behind a fake wall when he was found.

The body of Quiroga Santa Cruz, who was killed in 1980, has never been found.

"I'm pretty sure Molina must know where the body is," Morales said, expressing hope that will bring closure to the victim's family, who never gave up on finding his killer.

Quiroga Santa Cruz vanished in July 1980 during a paramilitary operation against the headquarters of a trade union that rejected the coup led by Colonel Luis Garcia Meza.