The families of two West Australian men missing in Mexico for more than a week say they are aware a "tragic event" has occurred, but still do not know exactly what has happened.

Loading

Dean Lucas and Adam Coleman were travelling in a van towards Guadalajara, but failed to arrive at their destination by November 21 as planned.

"The families and partners are aware the van in which they were travelling has been located by Mexican authorities and that a tragic event has occurred," the families said in a statement released by DFAT.

"The families hold deep fears for the safety of their sons but stress that they are still waiting for details to be confirmed."

Mr Lucas had been due to board a flight to London in a few days' time, said his Canada-based girlfriend, Josie Cox.

Ms Cox has tried to harness social media in an attempt to locate them, and is using the hashtag #finddeanandadam.

In a Facebook post, Ms Cox said the last confirmed sighting was when they got off a ferry at Topolobampa late on Friday, November 20 at 10:00pm.

Ms Cox said she was flying to Mexico today to meet Mr Coleman's girlfriend, Andrea Gomez, to coordinate a search.

Ms Cox said the men's disappearance had been reported to local authorities who had officially classed them as missing persons.

WA man planned move to Mexico

Mr Coleman's girlfriend, Andrea Gomez, speaking to the ABC via Facebook messenger from Guadalajara, where she lives, said she met Mr Coleman about a year ago.

She said after meeting Mr Coleman on the beach in the Mexican town of Tecoman, he would visit her in Mexico every two months.

"That's how we got to know [each other] and starting out on this journey in Mexico," she said.

"He was going to move in with me to my city. I already had three months without seeing him."

She said he bought the van to move to Mexico after his work contract ended in Canada.

Ms Gomez said Mr Coleman spoke perfect Spanish, but that her English was not very good.

When asked if there were any updates, Ms Gomez said they had some information but certain facts needed to be clarified.

"We must ensure certain information," she wrote.

"Tomorrow I will meet with Josie (Cox), she will travel from Canada to Puerto Vallarta."

She said she wanted to compare information with Ms Cox face-to-face.

"We need to reach some agreements on the information we have at this time," she said.

Ms Gomez told the ABC the situation had left her heartbroken.

"My soul is shattered, hopes continue however whenever this more hatred becomes, and more real actually this is a fact that will change my life," she said.

"Mark forever Adam, mark me forever. I can not think, my ideas are intertwined with each other so we just have to stay calm in this situation, make positive and with this attitude I guess things can get better soon enough."