Argentinian police have arrested a man and his nephew in connection with the death of a New Zealand tourist in Mendoza in April this year.
Nicholas Heyward, 31, was shot dead when two motorcycle-riding robbers tried to snatch his bag in a park in the city.
A journalist at the Buenos Aires Herald, Jayson McNamara, has been in contact with prosecutors in Mendoza.
"On Tuesday police carried out a series of four raids on the outskirts of Mendoza. They arrested a 34-year-old man who they allege was the shooter in the Nicholas Heyward case."
Mr McNamara said a nephew of this man later gave himself up to police over another matter and was then arrested in relation to this case.
He said at this point charges have not been laid because more evidence is being sought.
Nicholas Heyward's murder prompted a large public protest in the city of Mendoza. About 600 people marched in the General San Martin Park on the weekend after he was shot dead.
Declan McGarvey, a reporter in Buenos Aires, said at the time that although those sorts of crimes were common in Argentina, Mendoza was known to be a safe provincial town.
He said people there were shocked and astonished that such a crime could happen in their town, and that was reflected in the protest.
Mr McGarvey said the marchers were calling for the provincial government to put a new security and crime prevention plan in place.