POLICE divers are searching Lake Awoonga near Gladstone as part of an ongoing investigation into the suspicious disappearance of Rockhampton pair Robert Martinez and Chantal Barnett.
The search started on Wednesday and is expected to continue until Friday. Police are conducting the search in a small area of the lake.
Several strong tip-offs given to police over the last month have led them to search the lake.
Detective Senior Sergeant Scott Moon, of the Rockhampton Criminal Investigation Branch, said police had recently been able to verify the pieces of information which kicked off their search on Wednesday.
Police spent the morning marking search areas in Lake Awoonga before divers entered the water just after lunch.
Detective Sen Sgt Moon said any area that was searched underwater was extremely challenging.
"You have many obstacles that could be underwater there, as well as visibility," he said.
Martinez, 26, and Barnett, 27, were last seen in the Rockhampton/Yeppoon areas in late February or early March last year.
Concerns were raised after the pair failed to make contact with family or friends.
Rockhampton CIB and members of the Homicide Investigation Group are continuing to investigate the couple's disappearance, and while they are pleased with information received from the public, they are still encouraging anyone with information to come forward.
"We are very confident that people residing in Rockhampton know what happened to Robert and Chantal and we will continue to appeal for any member of the public to speak with police," Detective Sen Sgt Moon said.
"Regardless of how trivial you think the information might be, please come forward and speak with police so the relevance of the information can be assessed by detectives."
Over the past year several tip-offs from the public have led to police searching areas around Mount Morgan, Mount Archer and a site near Port Curtis.
Police and SES personnel scoured the banks of the Fitzroy River near Midgee in November after detectives received specific information surrounding their disappearance.
On all occasions the searches yielded no trace of the missing couple.
Police announced in September that the case was being treated as a double homicide.
Officers have previously located Martinez's wallet, car and some jewellery. Bank accounts belonging to the pair have not been touched since they disappeared.
The Martinez and Barnett families last month made an emotional plea for answers from the public.
On the Facebook page 'Help Find Robert Martinez and Chantal Barnett', a family member posted the following message: "One year ago tonight was the last time I seen you, spoke to you. Didn't get to say I love you or hug you or goodbye.
"I fell asleep on the couch, you didn't want to wake me, I miss you so bad everyday... this is so very wrong.
"Robert, we just want you home as do Chantal's family and her kids... they miss her so.
"If anyone has any more info, even the slightest, please do the right thing. This is hurting so many people... hold on and pray."
In February a forensic squad and other police units found clues at Parkhurst Country Club's cabin 26 that could help in the investigation.
Police have always maintained they believe they have spoken to someone who knows something about the pair's disappearance.
Anyone with information should contact Crime Stoppers anonymously on 1800 333 000 or crimestoppers.com.au.