GALENA PARK, Texas (KTRK) -- Students in Galena Park ISD are headed back to school on Tuesday after a pair of tragedies took the lives of four teenage students from the district.
Last Thursday, 17-year-old Marcos Orta was shot and killed in the parking lot of the Galena Park Community Center, which shares property with the high school.
For the first time in four days, students in Galena Park ISD will head back to class after their community has been rocked by tragedies.
Days after Orta was shot and killed, there are candles, balloons and messages for the teen outside the community center.
As classes resume on Tuesday, police released the mugshot of the teen charged in Orta's murder.
READ MORE: Shooting that killed Galena Park HS senior near campus may have been drug-related, police say
Johnny Lewis was arrested on Friday, the day after the shooting, and charged with robbery and murder.
Detectives said Orta met up with a group of people at the community center. At some point, shots were fired during an altercation.
Investigators are trying to figure out if the shooting was possibly drug-related.
Orta's friend said he heard three shots before spotting Orta on the ground, where he sadly died.
Friday was a district holiday and Monday was Presidents Day, so students have been away from campus for several days as the investigation has been unfolding.
Harris County Sheriff's Office investigators are trying to track down a second person they say was also at the murder scene.
SEE ALSO: Sources identify man accused of killing 3 teens in murder-suicide, sexually assaulting another
The Galena Park community is also remembering three teenage girls who were killed in a murder-suicide on Saturday night.
Law enforcement sources identified their killer as 38-year-old Humberto Valdez-Saldana, also known as Valentin.
He's accused of shooting and killing a 14-year-old neighbor, along with two of his girlfriend's daughters.
After the shootings, deputies say Valdez-Saldana sexually assaulted the victims' 12-year-old sister before killing himself. The 12-year-old managed to escape with her 1-year-old niece.
A family friend identified two of the victims as 19-year-old Sayuri Gil, who was six months pregnant, and 13-year-old Melany Torres. They were the older sisters of the 12-year-old, and Sayuri was the mother of a 1-year old. Both of them survived.
The third victim was identified by her family as 14-year-old Laisha Perez, who lived in the neighborhood.
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