Separately, six municipal councillors in the neighbouring Northwest Region -- another seat of anglophone unrest -- were also released in operations that saw "tens of assailants neutralised, huge stocks of weapons and ammunitions as well as large quantities of drug(s) seized," it said.
Cameroon's government is fighting insurgents demanding a separate state for the two regions.
They are home to most of the country's anglophones, who account for about a fifth of the predominantly French-speaking population.
The tourists, members of an organisation called the African Adventure Group, were seized in the area of Moungo-Ndor while they were heading for a tourist site called the Twin Lakes, the ministry said.
The lakes, lying in volcanic craters, have special significance in the local traditional religion and are deemed to represent the male and female genders.
The statement did not say when the group, or the municipal councillors in the Northwest Region, had gone missing.
One of the main armed separatist groups, the Ambazonia Defence Forces (ADF), played no part in the tourists' abduction, its leader Cho Ayaba told AFP.
Two other foreigners, a pair of Tunisian engineers, were abducted in the troubled region on March 15.
One of them died during an army rescue operation on March 20 -- "killed by his abductors," according to the military's account, which said "four terrorists died in the operation".
The anglophone question in Cameroon dates back to the colonial period in Africa.
France and Britain divided up the former German colony under League of Nations mandates after World War I.
A year after the French-ruled territory became independent in 1961, the southern part of British Cameroons was integrated into a federal system, scrapped 11 years later for a "united republic".
In recent years, agitation has risen among anglophones, chafing under the perception that they suffer prejudice at the hands of the francophone majority, especially in the judicial system and education.
But demands for a return to the federal structure were rejected by the government.
In a spiral of radicalisation, the breakaway movement issued a symbolic declaration of independence for "Ambazonia," their name for the putative state, on October 1.
President Paul Biya met the revolt with a crackdown, including curfews, raids and restrictions on travel.
Unrest has increased in recent weeks, with attacks on security forces and civilians as well as a spate of kidnappings of officials, and new groups are spawning within the separatist movement.
The clashes have prompted around 33,000 people to flee to neighbouring Nigeria.
The latest violence comes on the heels of visits to the Northwest and Southwest regions last month by Cameroon's newly-appointed interior minister, Paul Atanga Nji, himself an anglophone.
He said he brought "a message of dialogue, a responsible dialogue, a dialogue with those who know that Cameroon is one and indivisible".