Nyako belongs to the All Progressives Congress (APC) while Fintiri is of the Peoples Democratic Party (PDP)
Fintiri was sworn-in by the state’s Acting Chief Judge, Justice Ambrose Mammadi.
After taking the oath of office, the acting governor said the impeachment of Nyako was a blessing to the people of the state.
Fintiri called on the people to join hands with his administration, saying that the task before it was enormous.
He reminded them that Adamawa was still under state of emergency and urged them to be law abiding.
The acting governor promised to pay the two months outstanding workers’ salaries and other allowances.
“This administration will do all that is possible to restore the lost glory of the state as well as improve the economic well-being of the people.”
Chieftains of the Peoples Democratic Party and members of the National Assembly were among dignitaries that witnessed the ceremony.
Nyako was removed on Tuesday afternoon after the House of Assembly deliberated on the report of a seven-man investigative panel that probed allegations of financial misconducts against him.
Seventeen out of the 25 members of the Assembly adopted the report after it was read by Fintiri on the floor of the House.
The report found the governor guilty of all the 16 allegations of gross misconduct levelled against him by the House.
The report was endorsed by all members of the panel.
The motion for the governor’s impeachment was moved by Jerry Kumdisi, the member representing Gombi State Constituency.
It was seconded by Kwamoti Laori, the Deputy speaker of the Assembly and member representing Numan State Constituency.
All the 18 members present at the meeting signed the resolution removing the governor.
The House also passed a motion that Fintiri should be sworn in as the state’s acting governor.
Nyako’s deputy, Bala Ngilari, had a few hours before the impeachment proceedings commenced, resigned.
This was to forestall his impeachment.
Fintiri read the resignation letter during plenary also on Tuesday.
Former Vice President Atiku Abubakar has warned against the excessive use of power by the PDP-led Federal Government, a tendency, he said, was not good for decent democratic practice.
Atiku, who was reacting to Nyako’s impeachment, said in a statement issued by his media office in Abuja that wielding the axe of impeachment against elected public office holders to settle scores by the PDP-led federal government would needlessly build up tension in the country.
The former Vice President said the reckless use of impeachment to settle scores could not have been the intention of the framers of the 1999 Constitution.
He said the frequency with which elective officials were being shot down by impeachment would destroy the whole purpose of inserting the impeachment clause in the Constitution.
He regretted that the use of impeachment to harass and humiliate perceived opponents by the PDP-led federal government would ultimately bastardize the spirit in which the constitution provides for the impeachment clause.
The former Vice President admonished the PDP-led federal government to take it easy in the way they use power, adding that the constitution was not meant to provide ammo to anybody to harass and humiliate opponents or force them out of office.
He criticised the use of financial inducements to influence the removal of perceived opponents from office. According to him, triumphalism in the suppression of opponents is a bad omen for democracy.