In Michigan City, four people were arrested on probable cause pending a probable cause hearing, regarding two robberies Wednesday night. Police says the first robbery occurred in the parking lot of Lighthouse Mall and the victim was a 55 year old woman. The second robbery occurred two-hours later in the three-hundred block of South Street where the victim was a pizza delivery driver. Police says a city-wide search began and just after 10:30pm, an officer was able to locate the suspect vehicle in the 41-hundred block of Franklin Street. Through the investigation, police report it was determined that both robberies were committed by the four people in the suspect vehicle. Arrested were three men, ages 20, 19, and 18, along with a 29 year old woman, all from LaPorte. An investigation continues and additional charges are expected. Anyone with any additional information regarding these robberies is asked to contact Michigan City Police.