Story highlights Police identify the suspect as Neil MacInnis, a student at New River Community College

A 4chan post under MacInnis' name says he has a gun and ends, "Wish me luck"

MacInnis is being held without bond in a Virginia jail

The two women he allegedly shot are being treated at hospitals

An 18-year-old student drove to a community college campus located inside a western Virginia mall on Friday, walked in, then opened fire -- wounding two women -- before being subdued by an off-duty security guard and two police officers, authorities said.

Christiansburg, Virginia, police Chief Mark Sisson identified the suspect Friday night as Neil Allen MacInnis, who he said was a student at New River Community College.

An item on the online forum 4chan -- posted at 1:52 p.m. Friday, three minutes before police estimated the shooting began -- said it was from Neil MacInnis, who wrote that he goes to the same community college's satellite campus in Christiansburg.

The post urged people to check out an online stream of the New River Valley Public Safety scanner and promised, "I'm gonna give y'all the details because the news never gets it right."

"I'm a bit nervous because I've never really handled a shotgun but a few times with the Christiansburg police," the poster said. "Anyways this is not a highscores game but actually a lesson (that's why I'm at school)."

The post then gave a link to a New River Community College personal webpage under MacInnis' name

"Wish me luck," it added.

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CNN could not immediately verify that the 4chan post -- which CNN tracked down hours before Sisson identified the suspect -- was written by MacInnis.

The Christiansburg police chief did acknowledge that authorities were looking into social media reports. Several elements mentioned in the 4chan post paralleled what Sisson told reporters Friday night, including that MacInnis was enrolled at the community college, lives in Christiansburg and attended that city's citizen police academy last year.

The webpage included in the 4chan post offered other corroborating details. A man pictured on that page, for instance, resembles the mugshot of MacInnis that Christiansburg police released on Friday night.

Sisson said the suspect got out of his car and walked into his college's campus at the New River Valley in Christiansburg around 1:55 p.m. Friday.

He then shot the two women, before being taken down.

"The suspect was in custody within five minutes," the police chief said.

A woman who works at a mall clothing store near the campus described a frenetic scene after the shots rang out.

"We were a little in disbelief at first, but we saw people running away from that area," Diana Greenman told CNN affiliate WDBJ

The victims were transported -- one by helicopter, the other by ambulance -- to hospitals for treatment of their gunshot wounds. There was no word Friday night on their conditions.

One of them worked part-time at New River Community College, while authorities were still working Friday night to ascertain what relationship the other victim had, if any, to the school, the police chief said.

Investigators also were trying to pin down whether MacInnis and the two women knew each other.

The police chief didn't offer many other details, including about the kind of weapon used, how the suspect got the gun and how many shots were fired. But he did say that police don't think other people were involved.

"We believe that MacInnis acted alone, and there are no additional threats to this community," Sisson said.

On Friday night, while the mall where he allegedly shot the women was shut down except for law enforcement authorities, MacInnis was in the Montgomery County Jail. He was being held without bond after being charged on two counts of malicious wounding and two counts of use of a firearm during the commission of a felony, Sisson said.