Milwaukee police officers arrested a third suspect early Sunday who was charged with taking part in the shooting of a Wauwatosa police officer last week.Thongsavahn Rodthong, 27, of Milwaukee, was arrested in the 400 block of N. 34th St. about 12:50 a.m., police said.Michael S. Dengsavang, 28, Paul M. Phonisay, 29, and Rodthong, all of Milwaukee, face up to 40 years in prison if convicted of the charges of attempted homicide, party to a crime. They also are charged with burglary. Rodthong and Dengsavang are charged with armed robbery as well.