Dutch police have arrested a third person on suspicion of involvement in the tram shooting in the city of Utrecht that left three people dead and five injured on Monday. Three people are now in custody – the alleged shooter, 37-year-old Gokmen Tanis, and two others who were also arrested on suspicion of involvement in the shooting, public prosecution office spokesman Ties Kortmann said on Tuesday. Tanis is being held on suspicion of manslaughter with a possible terrorist motive, Kortmann said, adding that investigations are continuing into what drove him to allegedly open fire in a tram, AP reported.