The teenager accused of murdering 10 people and wounding another 10 during a shooting rampage at Sante Fe High School confessed to targeting students he disliked, but punked out on a plan to commit suicide after his killing spree, authorities said.

Dimitrios Pagourtzis, 17, used his father’s shotgun and .38 revolver during the school shooting, said Governor Greg Abbott in a news conference. Private journals in the Texas student’s computer and cell phone detailed plans for Friday’s attack, authorities added.

“Not only did he want to commit the shooting, but he wanted to commit suicide after the shooting,” Governor Abbot told reporters, adding that Pagourtzis admitted to the police that he “didn’t have the courage” to follow through on his plan to kill himself afterward.

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The governor also noted that explosive devices were found in the suspected shooter’s home. Pipe bombs and pressure cookers were later found inside and near Sante Fe High School.

Pagourtzis is being held without bond on charges of capital murder and aggravated assault on a public servant. Galveston County Magistrate Mark Henry, who denied bail for the student, noted that the suspect has cooperated with police. A probable cause affidavit, detailed by CNN, says Pagourtzis targeted people he did not like and spared people he did like so that he could have his “story told,” according to the New York Times.

Harris County Sheriff Ed Gonzalez confirmed that a second person is being detained.

At least 13 more people were being treated for shooting-related injuries at three area hospitals, CNN reported.

Classmate Tristen Patterson told Time that Pagourtzis enjoyed playing violent video games and talked about guns, but “never talked about killing people or anything like that.”

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President Donald Trump expressed his condolences in the wake of a school shooting tragedy, but, once again, offered little more: “This has been going on too long in our country. Too many years, too many decades now. We grieve for the terrible loss of life and send our support and love to everyone affected by this absolutely horrific attack. To the students, families, teachers and personnel at Santa Fe High: we’re with you in this tragic hour and we will be with you forever.”

The shooting at Sante Fe High School marks the 22nd school shooting in the U.S. since January.

In February, 17 people—mostly students—died in a mass shooting at Stoneman Douglas High School in Parkland, Florida. That shooting, among the 10 deadliest mass shootings in the U.S., led to nationwide student-organized protests calling for more restrictive gun legislation.

Houston Police Chief Art Acevedo took to Facebook Friday evening to express his disgust with yet another mass shooting of children, and an apparent refusal by elected officials to do much about them.

“I’m not ashamed to admit I’ve shed tears of sadness, pain and anger,” Acevedo wrote. “This isn’t a time for prayers, and study and inaction, it’s a time for prayers, action and the asking of God’s forgiveness for our inaction (especially the elected officials that ran to the cameras today, acted in a solemn manner, called for prayers, and will once again do absolutely nothing).”