A 29-year-old refugee who recently arrived in this country from Cuba was arrested at his Northeast Washington home early yesterday in connection with the murder of a retired Washington high school teacher whose bound and gagged body was found Monday floating in the Patapsco River near Baltimore's Inner Harbor.

Police identified the suspect as Raul Suarez Ramirez, 29, of 1231 Kearney St. NE, one of serveral houses owned by the victim, Armand Labat. Ramirez was arrested on a fugitive warrant and was arraigned yesterday before Superior Court Judge Ricardo Urbina, who addressed Ramirez -- who speaks little English -- in Spanish. Ramirez will be sent to Baltimore to answer a warrant charging that he murdered Labat. The body of the retired teacher of Spanish was found in Baltimore, but investigators have not determined where he was slain.

According to police, Ramirez and an unidentified male companion, described as a 28-year-old Cuban refugee, were seen driving Labat's 1976 white Lincoln Continental in Adams Morgan, a Northwest Washington neighborhood with a large Spanish-speaking population. The car was recovered in the 2400 block of Ontario Road NW, police said. A warrant has been issued for Ramirez' companion, they said.

Labat, a bachelor, was well-known in the Spanish-speaking community, police said, and hae rented his Kearney Street home to Ramirez. Police said that Labat had twice evicted Ramirez, but that the latter had been allowed to return to the house each time.

Medical examiners in Baltimore yesterday ruled that Labat, a member of a family prominent in the D.C. school system, had been strangled. His body was recovered six days after his family had reported him missing from his home on Quincy Street NW.

Labat taught Spanish at several Washington high schools and was a part-time teacher at the Adult Education Center at 33rd and R streets NW in Georgetown.