Thousands of Ecuadorian soldiers and police have been involved in a dawn operation to move a notorious gang leader to a maximum security jail.

Jose Adolfo Macias, known as "Fito" is accused of sending death threats to Ecuador's murdered presidential candidate, Fernando Villavicencio.

The anti-corruption campaigner was shot three times in the head leaving a campaign rally on Wednesday.

Before his murder, Mr Villavicencio said he had been threatened by Fito.

"If I continue... mentioning Los Choneros [the gang], they are going to break me," he said.

His death has shocked a nation that has largely escaped the decades of drug-gang violence, cartel wars and corruption that have blighted many of its neighbours. Crime has however shot up in recent years, fuelled by the growth of Colombian and Mexican drug cartels.

On Saturday, his Construye party announced his running mate, Andrea Gonzalez as its presidential candidate in Mr Villavicencio's place.

Ms Gonzalez's career has largely focussed on environmental issues, and the party said she would "guarantee the legacy" of Mr Villavicencio.

Meanwhile, Mr Villavicencio's widow Veronica Sarauz said she held the state responsible for her husband's death, and said she was unhappy Ms Gonzalez had been named as her husband's replacement to contest the election.

Mr Villavicencio's campaign focused on corruption and drugs. He was one of the only candidates to allege links between organised crime and Ecuadorian government officials.

The day before his assassination, he complained to the Public Prosecutor's Office about alleged irregularities in oil contracts negotiated during former president Rafael Correa's administration which had cost the country US $9bn (£7 bn).

Six Colombians have been arrested in connection with the murder, while a seventh was killed in a shootout. The authorities have not said who hired and paid the hitmen.

Gang leader Fito had been held in Prison 8 in Guayaquil since 2011, and videos shared by security forces showed him handcuffed in his underwear as security forces moved him to another facility.

Ecuador's President Guillermo Lasso said Fito had been moved to La Roca, a 150-person maximum security prison that is part of the same complex.