Authorities shut down independent TV stations, as security in the Kenyan capital was tightened ahead of the self-declared inauguration.
Mr. Kenyatta warned media not to cover the unofficial swearing-in event, with the chief prosecutor describing the ceremony as tantamount to treason.
Heavy police deployment was withdrawn Tuesday without explanation at the Uhuru Park where the opposition had said the event would take place.
The constitutionally recognized president is Uhuru Kenyatta who took office in November 2017 after winning a presidential poll rerun ordered by the court in September 2017. The unrest was tribal as well as political, with members of Odinga's tribe seeking to break the dominance of ethnic groups that have dominated the central government since the 1960s.More news: Ireland to hold abortion vote in May
The announcement by the National Super Alliance sets the stage for another round of election-related clashes between police and opposition supporters and raises fears of more civilian deaths.
Mwenda Njoka, a spokesman for the Interior Ministry, said the designation was a response to the symbolic oath of office that Odinga took Tuesday.
A tweet by D I K E M B E said that the swearing in of Raila Odinga was no longer about Raila Odinga.
After boycotting October's election rerun, Odinga has continued to contest the president's legitimacy, culminating in today's ceremony. That came after at least 67 people were killed during protests after the first vote, according to Amnesty International and Human Rights Watch.
The aim is for the opposition leader to become "the people's president" heading a shadow parliament. Kenyatta had "expressly threatened to shut down and revoke the licenses of any media house" that aired live broadcasts, the Kenya Editors Guild said in a statement.More news: Cleveland Indians Will Remove 'Chief Wahoo' From Uniforms In 2019
Wachira Waruru, the managing director of Royal Media Services, which owns Citizen TV, said they are actively engaging the relevant government authorities to establish the reason for the action and hope to resume normal transmission soon.
NASA is considered the victor of the presidential elections held last August, which were annulled by the Supreme Court.
Mr Musyoka did not say where he had been at the time of the ceremony at Uhuru Park and what prevented them from making their way to the venue.
Anther opposition supporter, vegetable seller Lilian Ondiek, 27, said she woke up at 4 a.m.to attend the event.
Odinga lost his bid for the presidency a year ago to incumbent Uhuru Kenyatta, but he says the voting was plagued by fraud.More news: Officer Who Pushed False Hawaii Missile Alert Believed It Was Real
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