Honolulu police have charged a 23-year-old man in connection with the robberies of four taxicab drivers over two months in May and June.

Titus Medeiros, who is believed to be homeless, is being held on $120,000 bail after being charged today with three counts of first-degree robbery, one count of second-degree robbery, and a probation violation charge.

The four victims, all men, worked for different local taxi companies. The robber used force, threatened his victims and, in three of the instances, displayed a knife while demanding money, police said.

 Police said they think the man robbed his first victim, 44, at the 2600 block of Kapiolani near the Marco Polo condominium towers at 9:24 p.m. on May 17; his second victim, 55, on Kapiolani just Koko Head of Date Street, about 1:50 a.m. June 18; the third, 58, near Date and Laau streets about 6:20 p.m. June 26; and the fourth,  53, on Kopke Street in Kalihi at 2:40 a.m. June 27.

 Detectives from the Strategic Enforcement Detail of the Honolulu Police Department’s Criminal Investigation Division arrested Medeiros by following up on leads developed by the Waikiki District’s Crime Reduction Unit that identified and located the suspect, police said.

 Medeiros has a criminal record and was sentenced to five years’ probation and $13,507 restitution earlier this year after being found guilty of second-degree burglary. Among the charges the suspect is now facing is violating the terms of his probation.