On Friday morning, seventeen-year-old Dimitrios Pagourtzis allegedly entered a high school in Santa Fe—a city of around 12,000 in the southeast Houston suburbs—with a shotgun and a handgun and killed ten people, wounding ten more. Because details are still emerging about the situation at Santa Fe High School, we’re focusing on including everything that’s been confirmed so far. The specifics are likely to be clarified as more information becomes available, but for now, this is everything we know about the situation on the ground in Galveston County.

What happened?
Several students at the high school told reporters that the shooting began after a fire alarm went off just before 8 a.m., at the start of the school day. Harris County Sheriff Ed Gonzalez—whose department arrived on the scene to assist local deputies—told reporters that ten people are dead, and the University of Texas Medical Branch in Galveston is treating three additional victims for injuries. Governor Greg Abbott said a total of ten people were wounded in the incident.

Who was shot?
Most of the victims are students, according to Gonzalez. Nine students and one teacher were killed in the shooting, and at least one of the people being treated for their injuries is a Santa Fe ISD police officer.

Who was the shooter?
As of 11:15 on Friday morning, Pagourtzis was in police custody, and a second person of interest was being questioned. It’s not clear at all if the second person is believed to be a second shooter or what role, if any, this person played in the shooting.

As we learn more about Pagourtzis, there’s also a lot of (seemingly deliberate) misinformation being spread. Multiple fake social media profiles in Pagourtzis’s name have appeared (most of them were quickly deleted). His actual Facebook and Instagram pages have been deleted since the shooting.

According to the Houston Chronicle, Pagourtzis used a variety of weapons in his attack—an AR-15 semi-automatic rifle, a pistol, a shotgun, and pipe bombs. It’s unclear if any of the explosives were detonated. The shooting is the worst in the United States since February. Abbott said the suspect used a shotgun and a revolver.

What was the motive?
No one knows right now.

It does come a few months after Santa Fe High School was placed on lockdown after “popping sounds” were heard near the school. There’s no indication that the two were related, and the February incident turned up no evidence of a shooting.

What happens now?
As of Friday afternoon, the school was considered an active crime scene, according to Gonzalez. Bomb squad and other police are still actively investigating as there are either reports or suspicions of explosive devices in the area. Responses to the shooting have already begun. Texas Attorney General Ken Paxton told students that his “thoughts and prayers” as well as those of the rest of the state were with them. Vice President Mike Pence told the students, “We’re with you.” Donald Trump said that “this has been going on too long in our country” and promised “to do everything in our power to protect our students.” Abbott went to Santa Fe, along with Lieutenant Governor Dan Patrick and U.S. Senator Ted Cruz, to meet with police for a briefing on the situation; the three later held a press conference to share some of what they learned. Cruz said that he and his wife would be keeping students, faculty, and first responders in their prayers. Democratic Senate nominee Beto O’Rourke tweeted that “my thoughts are with the community.” Democratic gubernatorial hopeful Lupe Valdez vowed, “We will act to make change,” while her runoff opponent, Andrew White, declared, “We must end this. Enough talk.” Texas House Speaker Joe Straus called on lawmakers to do something next legislative session.

The students themselves, meanwhile, are reacting viscerally to the tragedy in their midst. One, a girl identified as Paige, told a reporter that she didn’t find the shooting hard to believe. “It’s been happening everywhere, so I always kind of felt like eventually it would happen here too,” she said.

Outside of the scene, a man in a Trump hat whose relationship to the school is unclear stood with a gun on his hip and an American flag in his hand, telling reporters that when he heard about the shooting, his first thought was to get to the school to “offer support” and “make America great again.”

In the post-Parkland climate, the idea that victims and survivors deserve a grace period where the tragedy they endured is kept apolitical has largely changed—discussing the politics of mass shootings and gun control now happens almost immediately, led by the survivors themselves. At Santa Fe, students organized and demonstrated against gun violence before the shooting, with a dozen gathering outside of the building for the national student walkout on April 20.

On social media, meanwhile, more information is beginning to trickle out, as people identify their own personal connections to the shooting.

All of this is still unfolding, and there’ll be more to learn in the hours, days, and weeks to come. We’ll update this post when relevant information is available.