GREAT MILLS, US - A student armed with a handgun wounded two classmates at a Maryland high school on Tuesday, officials said, in an outburst of campus violence just days before a student-organized nationwide march for gun control.

The shooter, who was not identified, has died following the incident at Great Mills High School, St. Mary’s County Sheriff Tim Cameron told reporters.

Trump slams ‘sick people’ for Texas bombings

US President Donald Trump on Tuesday denounced a series of package bombings in Texas, calling those behind them “very, very sick” following an explosion Tuesday at a FedEx facility that officials said appeared to be linked to four others in Austin.

Until now, the spate of blasts that began in early March had been contained to Austin, the state capital with a population of nearly one million, where two people were killed and several more injured.

But just after midnight, a package exploded at a FedEx distribution facility in Schertz, outside San Antonio. Authorities would not confirm media reports that the package contained metal shrapnel and nails.

There were no serious injuries in the latest blast, but state attorney general Ken Paxton said the blasts were related. “It was mailed from Austin, it was to an Austin resident, and it blew up on the conveyor belt,” Paxton told KXAN.

US Congressman Michael McCaul, the head of the House Homeland Security Committee who said he has spoken to law enforcement, told KXAN: “All these devices are very similar.”

A second package that did not detonate was found at the Schertz facility, roughly 65 miles (105 km) southwest of Austin - a break in the probe that hopefully will provide clues to investigators, who so far appear to have few leads.

Hours later, another FedEx facility near the Austin airport was evacuated as police responded to reports of a suspicious package there, but officials provided no further information.

“The bombings in Austin are terrible. Local, state and federal law enforcement working hand in hand to get to the bottom of it,” Trump said, in his first public response since the crime wave began. “This is obviously a very, very sick individual or maybe individuals. These are sick people, and we will get to the bottom of it.”

“We have no clue who this is, absolutely no clue,” Texas congressman Brian Babin told the Fox Business network.

“I’m sure the FBI and the law enforcement agencies that are looking into this have some tips, some clues, but I haven’t heard anything about it.”

Senator Ted Cruz said he had spoken to the city’s mayor and police chief about what he called “coordinated attacks,” saying no effort should be spared to catch the bomber and “put him behind bars before anyone else’s life is at risk.” “It’s truly horrific what is happening in Austin,” Cruz told reporters in Washington.

Austin’s police chief Brian Manley said the bombings seem to be evolving.

The first three explosive devices were concealed in packages left at residents’ doorsteps. A fourth was detonated with a tripwire, which Manley said suggested a perpetrator who “shows a higher level of sophistication, a higher level of skill” than initially believed.

“And with what just occurred in Schertz, Texas, we’ve now brought in a new element that that device was actually going through one of the carrier services, instead of being hand-delivered,” Manley told a hearing of the Austin city council.

More than 1,200 calls have come in from residents since police urged them to report suspicious activities and items, Austin police said.

“I will reach out to the suspect or suspects and ask that you contact us... communicate with us so that we can put this to an end,” Manley said.

Authorities increased the reward offered for information leading to an arrest, bringing the total bounty to $115,000.