Quito, Aug 11 (IANS): Six suspects arrested in connection with the assassination of Ecuadorian presidential candidate Fernando Villavicencio and another accused who was shot dead are all foreigners, police have confirmed.

The six armed suspects, all members of organised crime groups, were captured hiding in a house in Quito, the country's capital, Xinhua news agency quoted a police report as saying.

Describing the killing as "a political crime of a terrorist nature", Interior Minister Juan Zapata confirmed all suspects are foreigners without revealing their nationalities.

The minister noted that the police will continue investigating and seeking a motive for the crime.

Villavicencio, the candidate for the presidential election which will be held on August 25, was killed on Wednesday in an armed attack following a political rally in Quito.

President Guillermo Lasso has decreed three days of national mourning and a 60-day state of emergency throughout the country "due to serious internal upheaval", which includes the mobilisation of the armed forces and the police to maintain order and public safety.

The assassination, which the government attributed to organised crime, occurred amid the electoral campaign for elections, which will go ahead as planned on August 20, Lasso said in a statement on Thursday night

The 59-year-old Villavicencio was a journalist and former National Assembly member, who forged his political career with a series of denunciations of corruption.

He was, according to polls, in fourth place for the upcoming elections.