Zairian authorities said they would issue a deportation order Friday for former Ugandan leader Idi Amin, who was arrested after arriving from Nigeria with a phony passport.

The hefty ex-dictator, blamed for the deaths of 250,000 Ugandans during his eight-year reign of terror, was recognized by hotel employees and arrested shortly after he arrived Tuesday in Zaire from the Nigerian capital of Lagos, officials said.Amin was expected to be deported Friday to Saudi Arabia, where he settled in exile after fleeing Uganda in 1979, Zairian officials said Thursday. The trip was his first known travel abroad since that time.

Sources at the Kinshasa airport said Amin came to Zaire with his son on an unannounced visit after a stopover in the Congolese capital of Brazzaville.

One source, who requested anonymity, said Amin arrived in Kinshasa bearing a false Zairian passport with an assumed name and then maintained the pretense under questioning by police.

Amin was recognized, identified, taken away in a police motorcade and interrogated at an undisclosed location, the source said.

Amin's visit was an apparent embarrassment to the government of Zairian President Mobuto Sese Seko, whose country shares a rugged 350-mile border with Uganda.