"This is very sad news for the Tuccaro family, and our thoughts are with them," said Staff Sgt. Gerard MacNeil. "This discovery brings us closer to finding out what happened to Amber."
MacNeil said a human skull was found east of Leduc on Saturday by horseback riders who immediately contacted police. Dental records confirmed that it belonged to Tuccaro, and her death is being treated as suspicious.
Officers have found other remains that are believed to belong to Tuccaro and are continuing to search.
Police said Tuccaro, 20, left her Nisku hotel room to catch a ride to Edmonton with a man two years ago.
She has not been seen since.
Tuccaro, who lived in Fort McMurray, was visiting Edmonton with her 14-month-old son Jacob and a female friend.
Last week, police released audio of a cellphone call in connection with the case, asking the public for help in identifying a male who was part of the call.
MacNeil said the response from the public has given investigators new leads.
"I would describe it as an exceptional response," he said. "From that we've received a substantial number of tips."
MacNeil said the release of the audio tape did not lead to the skull being found.
Tuccaro's family asked for privacy after the discovery was announced.