Twenty Nigerian medical students who were kidnapped on their way to a convention have been freed more than a week after their abduction, police said, Paralel.Az reports citing Al Jazeera.

Gunmen seized the students on August 15 as they travelled to a conference in Benue State, in the centre of the country, and later demanded a ransom.

“We confirm the release on Friday of our brothers and sisters and some other Nigerians who have been in captivity in Ntunkon forest, Benue State,” Nigerian police spokesman Olumuyiwa Adejobi said on Saturday.

State police said in a statement that they had “confirmed the release of the 20 students from the University of Maiduguri and University of Jos”.

The students were freed “without any ransom paid”. The group was “rescued tactically and professionally”, according to Adejobi.

The country’s police chief had this week deployed a “tactical squad” in Benue State as part of efforts to find the latest victims of a rising wave of abductions in Africa’s most populous country.

Fortune Olaye, secretary-general of the Nigerian Medical Students’ Association (NIMSA), also confirmed the release to the AFP news agency. “We’ve spoken to them on the phone. They are safe,” Olaye said.

The students were abducted while on the road in a convoy of two buses near the town of Otukpo, less than 150km (93 miles) from Enugu, which often witnesses attacks and kidnappings.