The van Mr Coleman and Mr Lucas were travelling in was found shortly after the men were reported missing in late November.
The parents of the men gave DNA samples to be matched with the bodies found in the van.
Mexican authorities made three arrests last week in relation to the murder of the two men.
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READ NOWSinaloa Attorney General Marco Antonio Higuera said undercover agents arrested three men who were pretending to be police officers and robbing drivers on the Mexico-Nogales highway.
He said the three men confessed to shooting Mr Coleman and Mr Lucas in their van.
Mr Higuera said one of the men confessed to shooting a long-haired man in the face and then shooting a second man.
The three men then reportedly drove the van to another location and shot Mr Coleman and Mr Lucas again.
The trio then said they set it on fire with Mr Coleman and Mr Lucas inside.
The burned out van was found on November 21, near Navolato, which is described as a town plagued with violence.
Mr Coleman and Mr Lucas were driving from Canada to meet Mr Coleman’s girlfriend Andrea Gómez in Guadalajara.
On December 13, surfers from around the world took part in paddle outs in tribute to the two men.