A teenager is charged in the deaths of four people, one of them a nine-year-old boy.
Police say the same suspect is responsible for a weekend shooting that killed a 29-year-old Gregory Watkins.
Flint Police and Michigan State Police worked in conjunction in this case.
They said tips poured in from the community concerning the July 15 triple homicide of a nine-year-old boy, his uncle and uncle's roommate.
Police said the suspect knew the three victims.
He used to live with them at the Park West Apartments in Flint.
Police said the suspect got into an argument with one of the men and two weeks later returned.
That's when another fight broke out, resulting in the triple homicide.
Police believe the suspect shot and killed the nine-year-old because he witnessed the murders and would be able to identify the suspect.
Officials said the same suspect also shot and killed 29-year-old Gregory Watkins and injured Demario Booth at the 12th Street Market Saturday, August 17.
According to police, the suspect accused the victim's family of owing him money.
Police believe the community input truly made a difference in this case.
"This case would not have been solved without Flint and Michigan State Police working together in conjunction with each other to get information, arresting the gentleman and locking him up," said Chief Alvern Lock, Flint Police.
In the triple homicide, the suspect is charged with two counts of first degree premeditated murder, felony murder, armed robbery and use of firearm.
In the weekend shooting, the suspect faces one count of first degree premeditated murder, one count felony firearm and assault with intent to murder.
Police say the investigation is ongoing.
The 18-year-old man is expected to be arraigned in 68th district court.