Sinaloa state Attorney-General Marco Antonio Higuera Gomez announced on Monday the torched van found on a dirt road next to an irrigation channel near the town of Navolato was the old blue and white striped Chevrolet owned by Mr Coleman. Two badly-burned bodies were found in the wreckage.
DNA testing will be undertaken and dental records checked by Mexican forensic experts to confirm if the bodies are the missing surfer mates from Golden Bay, south of Perth.
Mexican authorities inspect a burnt out van belonging to West Australian surfers Dean Lucas and Adam Coleman in Sinaloa, Mexico. Source: AP
Mr Gomez said Mexican officials had agreed to assign a special group of investigators to find the people responsible for the apparent murders, Mexico's Cadena news website reported.
The men, both 33, had been living and working in Edmonton, Canada, and drove the van down to Mexico for a surfing safari and to catch up with Mr Coleman's Mexican girlfriend, Andrea Gomez.
The van's Canadian number plates verified it belonged to Mr Coleman. Mr Lucas' English girlfriend, Josie Cox, flew from Edmonton to Mexico to be with Ms Gomez and help authorities with the investigation. In a Facebook post accompanied by photos of herself smiling with Mr Lucas, she announced she would embark on what her boyfriend apparently couldn't.
"Doing what Dean Lucas would've wanted, finishing his surf trip off....see u at the ocean Hun! Love and miss u soooo much," she wrote. Mr Coleman's sister Sarah Cattermole described her brother's love of travel.
"Your love for life and adventure is too extreme to even put into words," she said.
"I have tears in my eyes but a big smile on my face. A man who says he surfed with the pair days before they went missing has written about the two days he spent with the West Australians in Northern Baja.
Tarhn Koerting says he met Mr Lucas and Mr Coleman near Santa Rosalillita, a small fishing town popular with surfers.
"They told us all about wanting to be in Guadalajara on time - Adam was so stoked - and Dean couldn't be more excited for his trip back to his woman and the next leg of their life together," Mr Koerting posted to an online fundraising page.
The men planned to drive from the port town of Topolobampo to Ms Gomez's home in Guadalajara on November 20, but did not make it.
The route took them through Sinaloa, the notorious state of the Sinaloa Cartel, headed by drug lord Joaquin "El Chapo" Guzman and deemed by US authorities as the most powerful organised crime group in the world.
Sinaloa is a centre for kidnappings, violent robberies and cartel blood-letting, with the US State Department warning "travel off the toll roads in remote areas of Sinaloa is especially dangerous and should be avoided".
