While 165 Swampscott Middle School eighth graders were touring the third floor of the U.S. Holocaust Memorial Museum on Wednesday, June 10, gunfire rang out on the ground floor just before 1 p.m. when two people were shot.

Approximately 200 eighth graders from the Holten Richmond Middle School in Danvers were also on a school trip and were on the fourth floor when the incident occurred, according to The Salem News.

While conflicting accounts are still coming in, CNN reports that an armed man entered the museum at 12:50 p.m. and fired at a security officer. A spokesman for U.S. Park Police said two other security officers at the museum returned gunfire. The security officer and the shooter were seriously wounded. They were transported to George Washington University Hospital where the security officer later died. The shooter is in critical condition. A third person sustained minor injuries apparently from flying glass during the incident.

The museum was evacuated.

The Swampscott eighth graders, who were accompanied by 16 chaperones, were telephoning their parents and the school Wednesday afternoon, reporting that they were all unharmed. Some reportedly said they heard the gunshots from the third floor. Assistant Principal Megan Bonomolo, who is on the trip along with several teachers, telephoned the school to reassure parents that their children are well.

Assistant Superintendent Dr. Maureen Bingham told the Journal at 2:30 p.m. (an hour after the shooting) that the class would be staying on schedule and going to lunch as planned.

“I have full confidence in our staff that they will keep our students safe,” said Bingham, sounding shaken. “Of course, I’m very upset. I have been to the Holocaust Museum. None of us yet knows anything about the motives of the shooter yet or what this could signify.”

Bingham said this is the third year Swampscott eighth graders have gone to the Holocaust Museum in Washington D.C. It was part of a four-day tour of the nation’s capital, which began Tuesday and is scheduled to end Friday when the class returns by bus.

Kara Ring of Swampscott said her child telephoned her shortly after the incident to say that everyone was fine.

A law enforcement source identified the gunman as James W. von Brunn, 88, who is known to authorities as a white supremacist, according to The Washington Post. The newspaper states that on a Web site he apparently maintains extolling a "Holy Western Empire," von Brunn says he served in the U.S. Navy during World War II, worked for 20 years as an advertising executive and film producer in New York and then became "an artist and author" living on Maryland's Eastern Shore.

According to a police source, law enforcement agencies using bomb-sniffing dogs responded Wednesday afternoon to more than 100 "targets" that were listed in a notebook found in the gunman's possession.

"The targets were listed in this guy's notebook," the source said. "We were told it was more than 100." The source did not have any details on the locations, states The Washington Post.