Two Canadian women were rescued after being abducted last week by armed men in Ghana's second largest city, Kumasi.
The two unnamed students, ages 19 and 20, volunteered for a charity when they were confiscated.
Abductions in Ghana, considered one of the most stable states in West Africa, are extremely rare.
There have been a few lately, however, that usually involved ransom demands.
In the early hours of Wednesday, security forces conducted an operation to rescue the women, Information Minister Kojo Oppong Nkrumah said in a statement with kidnappings in the country.
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The leader of Ghana's main opposition party, the National Democratic Congress (NDC), was briefly arrested by police on Tuesday as a suspect in kidnapping.
"Credible and actionable intelligence services" led to the arrest of Samuel Ofosu-Ampofo, police said in a statement posted on Twitter, without stating which abductions he was allegedly associated with.
Mr. Ofosu-Ampofo has not commented on the allegations, but NDC Secretary General Aseidu Nketia said his arrest is an attempt to "intimidate us and thwart our activities."
In April, an Indian was arrested in Kumasi by an armed gang demanding a ransom. He was later rescued by the police.
An Estonian diplomat was also rescued by the police after being abducted in the capital in April, Ghanaweb reported.
The police are still looking for three Ghanaian women who were abducted by Takoradi in December in the southern city.